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7 C of Communication

2020-01-01T01:16:00.000+05:00

The Seven C's of Communication.

Clarity
Coherent
Correctness
Conciseness
Concreteness
Completeness
Courteousness

Effective Communication involves the use of all above mentioned 7 C's of Communication. Effective Communication is the key to being productive in today's busy life. Most of the jobs mention that the person applying should have good communication skills.

A study conducted by McKinsey Global Institute reveals that employees spend about 30% of their time on emails and remaining time is spent in meetings, conference calls, presentations, report writing and other such activities. Therefore, it is necessary to have a proper understanding of 7 C's of Effective Communication to be productive.

Clarity:

Anything you say, you should say it in clear and simple words, otherwise the listener will assume things and will have to come back again and again for asking what you meant.

Coherent:

All the sentences in your message should relate to each other so that the receiver do not gets confused whether you are talking about one thing or another.

Correctness:

It is necessary to provide correct information when communicating with someone about any task. By correctness, it is meant that you should tell correct instructions or information such as name of location where a meeting is to be held or date of the function or ceremony etc

Conciseness:

Whatever you want to say, just say it with words that will best describe your purpose. Use words which are simple and used in our daily life so that the other person do not need to waste time thinking about actual meaning of your words.

Concreteness:

Just like the word "concrete". your message should be so much strong that it leaves an impact on the listener and allow him to get the idea that whatever you said is true and important.

Completeness:

It is utmost necessary to provide complete information in addition to being clear and correct. If you are writing an invitation for a party, be sure to mention where the party is going to be held, at what time will it start and on which day you will be expecting people to come.

Courteousness:

Being courteous is the sign that you value other person and their time which will make them realize that they should listen to your message carefully. Unnecessary frames and hidden insults can lead to spoil a healthy working relationship.

Effective Communication

2019-12-28T20:46:00.001+05:00

By Definition: Effective communication refers to the method of relaying information that gets a point across. (WikiEducator)

In simple words, effective communication leads to understanding.

For effective communication, the Sender should speak in clear and simple terms whereas, Receiver should listen actively to understand the message.

There are many factors which affect how our Communication can become Effective, some of which are being listed and explained here.

Body Language:

The most important part of any verbal conversation (in which persons can see each other) is how the person talking uses his body language to match his words. This is also important in face to face meetings and video conferences. Make sure that you appear accessible, so have a open body language.

Open body language means you should not cross your arms and keep eye contact so other person knows that you are listening.

Consideration of Listener/Audience:

It is okay to use acronyms and informal language when we are talking with a friend but we can not use words like "Hey" or "Whats up?" with a Professor.
Different acronyms have different meaning to different people, which can lead to misunderstanding of the message.

If you are a teacher in a class room of IT students you should provide technology related examples while teaching them but if you are in a class room of biology students then you would consider environment and nature related examples.

Right Interpretation of the Message:

One should listen carefully to what the other person is saying. Instead of formulating your response, ask for clarification to avoid misunderstanding. At that moment, the person you are listening to should be the most important person in your life.

You can not multitask if you want effective communication, for example if you are listening to a phone call and at the same time talking with person in front of you, then at times you won't be able to understand completely what both the people talking to you are saying.

Be Brief but Specific:

For written and verbal communication, you should provide enough information for the other person to understand what you are saying but use simpler words.

Do not use very complicated words, only choose the words which are used more normally in our daily life, for example if we use words like Room in place of Accommodation, Buy in place of Purchase and Use in place of Utilize then my communication will become brief but specific to my context.

What is Mole?

2018-06-09T02:50:00.001+05:00

Mole is the unit of the Amount of Substance of any matter
It is written as "mol" for short.
Same number of moles of different substances contain same number of particles.
Same number of moles of different substances possess different mass.
The amount of particles present in 1 mole of any substance is 6.02x10 (which is also known as Avogadro's Number)

Related Links:
What is Avogadro's Number?
Who invented Avogadro's Number?

What is System of Forces with Practical Examples

2018-04-17T03:34:00.000+05:00

What is System of Forces?

When two or more forces act on a body, they are called to form a system of forces.
There are various systems of forces mentioned below with their day-to-day examples.

Collinear Forces:

Collinear forces are forces which have a common line of action, i.e. the line of action of the forces lie along a single straight line.

Examples:

Two people standing at the opposite ends of a rope and pulling on it.

A Suspended load by a cable

If two people push a box standing adjacent to each other and both pushing in the same direction, then it is collinear as they can not intersect each other.

Co-Planar Forces:

When, the line of action of the forces lie in the same plane, the forces are called Coplaner.

Examples:

When a boy skates down a hill, two forces act on it in the same plane.
Force A: Weight of the boy acting downward
Force B: Force of acceleration acting along the hill on some angle.

When someone rides in a RollerCoaster and rollercoaster reaches some height then three forces act on the rollercoaster in same plane.
Force A: Force of weight acting downward.
Force B: Normal reaction of rollercoaster which is in opposite diirection of weight.
Force C: Acceleration of the rollercoaster at some angle.

When a weight a pushed upwards on a slope three forces act on it in the same plane.
Force A: Weight of the box acting downward
Force B: Normal reaction of the box acting upward.
Force C: Force which pushes the box at an angle on the slope.

Concurrent Forces:

Concurrent forces means a system of force whose line of action meets at one same point.

Examples:

When a barge is pulled by two tug boats using ropes tied on a same point on the barge, two concurrent forces along the ropes are pulling the barge.

Suspension cable with a common end having weights suspended on it.

If many people stand the ends of a rope and pull on it in a tug of war, the forces are concurrent because the effect of the forces will intersect at the same point (presumably in the middle of the rope).

Non-Concurrent and Co-Planar Forces:

Nonconcurrent and coplanar forces are two or more forces whose magnitudes are equal but act in opposite directions with a common line of action in the same plane.

Examples:

When driving a car your hands are opposite to each other on the steering wheel. The forces you apply with both hands when turning, one hand pushes while the other pulls the steering wheel.

When a cyclist pedals, his or her feet are parallel. One foot pushes a petal forward while the other pushes the other pedal backward. These two forces cause the wheels on the cycle to rotate.

When two people sit on the opposite sides of a seesaw and swing it upward or downward by pushing the ground alternatively they form a system of two non-concurrent and coplanar forces.

Concurrent and Co-Planar Forces:

Concurrent and coplanar forces means the line of the action of the forces meets with each other at one same point and lies the same plane.

Example:

When a car is driven on a road in real life the force of friction and force of acceleration of the car acts on the car means they have a same point which is car and they lie in the same plane.

When a load is suspended load by one or more cables, the gravity which acts downward and the cables which act upward have a same concurrent point i.e load, and they lie in same XY plane.

The ceiling fan is acted upon by force of gravity downward the force of tension which keeps it upward, both of these force acting in the same plane acts on the ceiling fan which means they are concurrent and coplanar.

What is Avogadro's number

2017-07-02T01:24:00.000+05:00

The fixed value of the amount of particles, atoms or molecules present in One Mole of any substance which was calculated by Amedeo Avogadro, an Italian Scientist who is most noted his contribution to the molecular physics and He was also the Count of Quaregna and Cerreto.

Avogadro's Number:

The amount of atoms, molecules or particles present One Mole of any substance is called Avogadro's Number.
The value of Avogadro's Number is: 6.02x10²³
Avogadro's Number is denoted by or The symbol of Avogadro's Number is: N_A

Example:

1 mole of H²O contains 6.02x10²³ molecules of water
1 mole of H contains 6.02x10²³ molecules of Hydrogen
1 mole of NaCl contains 6.02x10²³ atoms of Na + 6.02x10²³ atoms of Cl

Other Important Links:
What is Mole?
Who was Amedeo Carlo Avogadro

References: Wikipedia

Tips and tricks for scoring highest in Entry Test of any University.

2017-06-08T11:08:00.000+05:00

The season is high with the trend of Entry Test as the students prepare desperately for passing in the admission test of their desired Universities. Students prepare and work hard all the time to clear their concepts but they forget that Entry Test is not about concepts alone rather it is a test of concepts as well as your time management.

Below are a few tips according to those who have passed the Entry Test, these will help you to achieve the best results and put your hardship of month to a good use.

Things to keep in mind for Entry Test:

Entry Test usually comprises of 100 M.C.Q questions and you get about one minute for each questions, but you should not divide this time equally for all questions. Maths questions should take more than one minute where as English questions take less than 30 seconds.

Do not read the choices immediately after reading the question, instead think about the answer in you mind first then read the choices and choose the most appropriate answer.

Every question certainly has some wrong choices so if you don't know an answer then use your common sense and think about answer after reading the question then narrow down the choices. This is best strategy when don't know an answer.

Keep in mind that answer sheets are computer sensitive. Usually there are boxes or circles which you fill with your pen then the computer scans the filled circles to give you marks, so fill the box or circle in such a way that computer easily detects it.

If a question is time taking then leave it for now, attempt other questions then come back for that question in last. This will save you from wasting many questions for just one question.

On the answer sheet when you fill the circles you should be extremely careful as I am sure you don't want to fill the circle of question 12 for the answer of question 11. The sheets are checked by computer, it will not give you mark for such a mistake.

Some students prefer to fill the circles altogether in the last after deciding the right choices for each question. This way one can save a lot of time by not filling circle one by one but it also require you to be careful not to circle the wrong question.

Be vigilant and quickly answer the questions but do so by using your head. Entry is all about time management and conceptual understanding. So do not act casual or formal in any case. This is the test for your future, you must not take it lightly.

Good Luck ^_^

Mole vs Molecule | Difference between mole and molecule

2017-03-23T04:17:00.000+05:00

Q. What is the difference between a mole and a molecule?

Ans:

MOLE: A mole is a fixed number, that is 6.02x10²³ it is also known as Avogadro's Number because Sir Avogadro was the person who calculated about 6.02x10 molecules and gave it the name "Mole". So mole is also used as unit for molecules. For example if we say one mole of hydrogen that means 6.02x10 molecules of hydrogen.

MOLECULE: A group of atoms is called a Molecule. There are approximately infinite molecules in any substance, we can not count exactly how many molecules are there in a substance. Each molecule is made by two or more atoms combined together by any type of bond.

So, we can conclude that a Mole is a fixed number and a Molecule is a group of atoms this is the difference between a mole and molecule.

Impact of Internet on Youth | Essay

2016-12-30T18:42:00.000+05:00

Internet today has become an inseparable part of our lives and irrespective of our age, profession as well as field, we are making use of internet in one way or another. Internet was introduced for passing messages to distance in short period of time and to access information but in this current world, it is being used for all purposes like study, news, entertainment, music, games as well as for vulgar material.

There is a good side as well as bad side of everything. It is good that internet is helping everyone to know things in very short time by sitting at home but out of all the people who use internet, teenagers are seen to be the biggest contributors of the use of internet. With virtual relationships and friendships given more relevance over the real ones, it has certainly become a topic of concern for parents that what type of content their children are exposed to over the internet and how internet is changing and developing their minds. In Pakistan, mostly students lose their moral values of life due to open access over the internet and exposure to immoral content. There are parental control software which can help parents to control which type of content their kids should access but these type software are relatively not easy for parents to understand and most of the parents do not even know how to use them.

In short, we can conclude that internet is great source of advantages and disadvantages for our youth. It depends on the person that what mindset he possesses and how he uses the internet

All about Sets

2016-11-06T02:39:00.002+05:00

Q. What is Set?

Ans: A Set is a well defined collection of distinct objects.
The elements of a set are called its members. The members are generally written in small alphabets while the set it self is expressed by a capital alphabet and the set is closed in curly brackets.

well defined means, something that can be defined in words and here distinct means "clear" so a set is a collection of things which we can clearly define.

for example:-

A set of chairs, A set of students, A set of students who read in class ten. etc

Q What are types of Set?

Ans. There are generally four types of sets.

1. Empty/Null Set:

A set which has no members or elements such a set is called Empty or Null set.

{x € R| 5<x>5 } = { } or ∅

2. Singleton Set:

A set which contain only one element is called a singleton set.

{x € R| 1<x<3 } = { 2 }

3. Finite Set:

A finite set is a set which has a limit, its member are in a fixed quantity.

{x € R| 1<x<10 } = { 2,3,4,5,6,7,8,9 }

4. Infinite Set:

Infinite set is the opposite of finite set. Its member have no limit and they are not countable.

{x € R| x>0 } = { 1,2,3,4,5,6,7,8,9, ... }

Geometry

2016-07-04T16:16:00.000+05:00

What is GEOMETRY?

Geometry is a branch of Mathematics. It is concerned with the relations of shapes and relative arrangement of parts or things such as points, lines, surfaces, solids and higher dimensional analogues. It is the most basic science and elementary form of mathematics

The word Geometry is derived from Greek word Geo (earth) and Metron (measure) which indicates that Geometry is actually a science to understand and perform calculations about earth.

Geometry was invented by a Greek mathematician Euclid, he was known as father of Geometry. It is considered as the oldest branch of mathematics and no one can tell exactly when it was invented although some records suggest that Geometry was first used in Egypt around 3000BC.

Trigonometry

2016-07-04T15:59:00.000+05:00

What is TRIGONOMETRY?

Trigonometry is a branch of Mathematics. It deals with the measurement and calculations of angles such as the sides or angles of a triangle. It is also used to find the area of such figures and trigonometry also deals with the specific functions of each angle of a triangle. It contain equations and principles which help us to solve trigonometric problems.

Trigonometry was invented by ancient Greek philosophers in Sixth century, Hipparcus, Menelaus and Ptolomy greatly contributed in the development of trigonometry.

What is ALGEBRA?

2016-07-04T15:43:00.002+05:00

Algebra is the branch of Mathematics, it deals with symbols and rules which manipulate those symbols. These symbols are actually letters of Greek and Latin languages. Algebra contain equations which helps us to solve problems in a systematic method.

Algebra was founded in 16th century by a Muslim mathematician Al-Khwarizmi, he invented many principles of Algebra also known as Al-jabr and thus he is known as the father of Algebra.

Scalars and Vectors

2016-07-04T15:17:00.000+05:00

Q. Define Scalar and Vector quantities with examples:-

Ans:-

Scalar Quantities: Physical quantities which can be denoted only by a number and a specific unit are called Scalar quantities. Scalar quantities do not have any direction and the value of a scalar is called its magnitude.
Scalars are added, subtracted, multiplied and divided by using simple rules of algebra.

Examples of Scalars:
work, energy, volume, time, speed etc

Vector Quantities: Physical quantities which are denoted by a number, a specific unit and also a particular direction are called Vector quantities. Vectors are defined by a magnitude along with a particular direction.
Vectors are added , subtracted, multiplied and divided by using rules of trigonometry and geometry. A vector is represented by capital letters with an arrow above them.

Examples of Vectors:
velocity, force, acceleration, torque, momentum etc

MOTION

2015-11-21T01:53:00.001+05:00

Q. What is Motion and its type..?

Ans:-

MOTION: Any object is said to be in state of motion if it moves or changes its place.

TYPES:

There are three types of Motion

1. Translatory Motion: If a body moves along a straight line or in a straight path it is called Translatory motion. For example, trains usually run on straight tracks they are said to be in translatory motion. Translatory motion can further be divided into three types

Linear
Rectilinear
Circular

2. Rotatory Motion: If a body rotates around its axis. It is said to be in rotatory motion. For example, our earth and other planets rotate around their axis there fore we can say that earth is in rotatory motion.

Note: There is a type of rotatory motion called Circular motion. The difference between Rotatory and Circular motion is that, in rotatory motion body rotates around its own axis but in circular motion body circles around the axis of another body)

3. Vibratory Motion: When a body moves to and fro continuously, it creates vibrations and there fore is said to be in vibratory motion. Vibratory motion is also known as Oscillatory motion. For example, the motion of a pendulum is a vibratory motion.

Hydrolysis and Hydration

2015-08-12T02:37:00.000+05:00

Q. What is Hydrolysis and Hydration?

Hydrolysis:

Hydrolysis is a process in which a compound breaks down into its substances due to reaction with water. It is a type of chemical reaction, hydrolysis involves adding a molecule of water which causes a bond between any other compound to break and then water replaces the molecule whose bond is broken. It can also be described as a type of single displacement or double displacement reaction which involves addition of water to decompose a specific compound.

Hydration:

Hydration is a process used to add water in to a compound or substrate in order to modify it. It is also a type of chemical reaction which involves the use of water to change a chemical or to modify it. Hydration can also be described as a type of addition reaction as this process is used to add water molecule into a compound.

Difference between Hydrolysis and Hydration:

Hydrolysis is used to add water into a compound in order to remove a substance and replace it with water whereas Hydration is used only to add water into a compound, it does not involve replacing or removing any mole from the compound.

Chemical Equation

2015-08-12T01:44:00.000+05:00

Q. What is Chemical Equation?

Chemical Equation:

The symbolic or short hand method of describing a chemical reaction is called Chemical Equation. In a chemical equation the symbols of substances reacting with each other are written on the left hand side, they are called Reactants and the compounds which are formed due to their reaction are written on the right hand side, they are called Products. An arrow between reactants and products represent the process of chemical reaction. Mostly single head arrow is used in chemical equations to show the process of reaction but sometimes a double headed arrow is also used between reactants and products, it shows that the reaction is a reversible reaction the reactants can become product and products can become reactant using the same process.

Double-headed arrow

Single-headed arrow

Types of Chemical Reactions

2015-08-11T22:50:00.001+05:00

Q. Explain types of Chemical Reactions with example:-

There are six general types of chemical reactions:

1. Combustion Reaction:

A Combustion reaction occurs when Oxygen reacts with any other compound to form Carbon Dioxide and water. It is a exothermic reaction which means heat energy is produced during this reaction.

Example: When methane gas (CH₄) reacts with oxygen (O₂) to produce one mole of water (H₂O) and one mole of carbon dioxide (CO₂)

CH₄ + O₂ =====> H₂O + CO₂

2. Addition or Combination or Synthesis Reaction:

A type of chemical reaction in which two or more compounds react with each other and form a single compound. In this reaction energy is released in form of heat and light.

Example: When one mole of carbon (C) reacts with one mole of oxygen (O₂) to form one mole of Carbon dioxide (CO₂)

C + O₂ =====> CO₂

3. Decomposition Reaction:

A decomposition reaction is the opposite of combination reaction. In this type of chemical reaction a single compound breaks down to form two or more compounds.

Example: When Hydrogen Peroxide (H₂O₂) is heated it decomposes into one mole of water (H₂O) and one mole of oxygen (O₂)

H₂O₂ =====> H₂O + O₂

4. Substitution or Single Displacement Reaction:

A reaction is called Single displacement or substitution reaction if one element in a compound changes its place with another element in a compound.

Example: When zinc (Zn) reacts with copper chloride (CuCl₂) as a result zinc changes its place and replaces copper from copper chloride to form zinc chloride (ZnCl₂) and copper is left alone.

Zn + CuCl₂ =====> ZnCl₂ + Cu

5. Double Displacement Reaction:

A reaction is called Double displacement reaction if two elements in their respective compounds change their partners to form new compounds. In a double displacement reaction usually anions and cations of two different compounds change their places.

Example: A reaction in which Potassium Iodine (KI) reacts with Lead Nitrate (Pb(NO₃)₂) and as a result potassium from the compound of potassium iodine changes its partner with lead in the compound of lead nitrate to form Lead Iodine (PbI) and Potassium Nitrate (KNO₃)

KI + Pb(NO₃)₂ =====> PbI₂ + KNO₃

6.Neutralization or Acid-Base Reaction:

It is a special type of Double Displacement reaction in which an Acid reacts with a Base. The H⁺ of an acid react with OH^- of a base which causes the formation of an ionic Salt and Water.

Example: When Hydrochloric Acid (HCl) reacts with Sodium Hydroxide (NaOH) and form Sodium chloride salt (NaCl) and water (H₂O)

HCl + NaOH =====> NaCl + H₂O

Chemical Reaction

2015-07-23T00:21:00.004+05:00

Q. What is a Chemical Reaction?

A chemical reaction occurs when two or more molecules interact with each other. They form bonds and create a new molecule.

In a chemical reaction, the molecules that interact with each other are called reactants and the molecules produced by the reaction are called products. During a chemical reaction, no new atoms are created or destroyed. A reaction could include atoms, ions, compounds or molecules of a single element. The reactants contact each other, bonds between the atoms are destroyed and they rearrange to form new bonds and as a result products are created.

Molecule

2015-07-23T00:21:00.003+05:00

Q. What is Molecule?

A group of atoms bonded together makes a molecule. Because an atom is so small that we cannot see it but when many atoms of same element combine together that makes a compound that is visible to our eyes and we can use it in reactions.

So.. The definition of atom is:

A group of atoms of same element bonded together.

Element, Compound and Mixture

2015-07-21T14:07:00.001+05:00

Q. What is an Element?

Any individual type of atom that is used to make a material is known as element. A single atom of any material for example an atom of Hydrogen is called as element.

For example, if we look at the periodic table it says: Periodic Table of Elements and there you can see the first element is H (Hydrogen) which shows the mass and atomic number of a single atom of hydrogen.

There fore, we can say that

a single atom of any material is known as element.

Q. What is Compound?

Two or more elements chemically joined together makes a compound. When we take two different elements and chemically combine them that makes a new element that is known as Compound.

For example, if we take two atoms of hydrogen gas (H2) and one atom of oxygen gas (O) and then chemically unite them that makes water (H2O) a new and totally different compound.

Q. What is Mixture?

Two or more substances mixed together makes a mixture but there is no chemical change or chemical bond between them. In a mixture the chemical properties of substances is never changed.

For example, the air we breath is also a mixture of different gases. Our air is mostly composed of Nitrogen, Oxygen, Carbon dioxide and some other gases.

Mass

2015-07-17T03:40:00.000+05:00

What is mass?

Mass is the quantity of matter present in a body. Remember mass is not weight. Don't confuse Mass and weight, they are two different things.

To explain it in more simple words, lets take an example: if you go to a general store and ask for 2 kilo-gram of sugar. The shopkeeper will give you a plastic bag filled with two kilo-gram sugar crystals. The quantity or the number of sugar crystals in that plastic bag is Mass of sugar and two kilo is the Weight of sugar.
If you concentrate and think carefully only then you will get the difference between Mass and Weight.

Well.. the definition of Mass is:

The quantity or amount of matter present in a body is called its mass.

Mass is the measure of how much stuff is present in an object. Mass is directly proportional to weight means if mass increases the wight will also increase but if put in a place where theres no gravity such as Space then there will be no weight only mass will be present in a body that is also the reason why it is really hard to stop or start moving a space shuttle in space.

Atom

2015-07-17T03:25:00.000+05:00

What is atom?

Atom is the smallest particle of any thing. Atom is so small that a human eye can not see it. You can think of an atom like the building block of anything. Tiny tiny atoms join together and make bigger things such as rocks, mountains, water falls, air and even humans and animals all are made up of atoms.
To give you a more clear idea of what an atom is take this example, The small bricks that if joined together one on one makes great buildings, just like those bricks the atoms join together and create matter as you know matter can be anything.

So the Definition of atom is:

The smallest particle of any element is called atom.

Atom is the smallest particle of anything however atom itself is made up of three small particles known as sub-atomic particles. The center of atom is called nucleus, inside nucleus two type of particles reside one is Proton and the other is Neutron. Proton is positvely charged particle where as Neutron has no charge or we can say that neutron is neutral. Outside the neucleus is some space and this space is filled by the third particle known as Electron. Electron is negatively charged and it keeps revolving around neucleus just as earth revolves around sun, interesting na? electron revolve in specific routes as shown in figure above and these routes are called electron shells or orbits.

Law of Conservation of Momentum

2015-07-13T13:07:00.000+05:00

Q. Explain the Law of Conservation of Momentum with the help of an example:-

Introduction:

One of the most powerful laws used in Physics is the Law of Conservation of Momentum which is given by Sir Isaac Newton, which states that:

Statement:

The total momentum of an isolated system before collision is always equal to the total momentum after collision.

Explanation:

Consider two bodies A and B, having mass m1 and m2, moving initially with velocities as v1 and v2. When body A collides with body B the velocities produced after collision are taken as u1 and u2 , on observing it is found that the total amount of mass and velocity of both bodies after collision remains same as before collision. This proves that the Momentum between these two bodies remain constant just as the Law of Conservation of Momentum says that momentum before collision is equal to momentum after collision.

Figure 1: Body A and B moving with initial velocities (v₁ & v₂)

Figure 2: Body A collides with body B

Figure 3: After collision their mass and velocity remains same (take u₁ & u₂ as velocity after collision)

Mathematically:

Formula for Momentum :-

m × v

Total Momentum of A and B before collision :-

m₁v₁ + m₂v₂

Total Momentum of A and B after collision :-

m₁u₁ + m₂u₂

Thus the total amount of Momentum before collision is equal to Momentum after collision:
m₁v₁ + m₂v₂ = m₂v₂

Note for students: You must be curious that why v₁ v₂ are used before and u₁ u₂ are used after collision. Well its because the velocity before collision is initial velocity and velocity produced after collision is final velocity, to differentiate between initial and final v & u are used. I hope u understood :)

Define Momentum

2015-07-13T11:56:00.001+05:00

Q. What is Momentum?

Definition:

The quantity of motion present in a body is called its Momentum. The amount of momentum in a body can be measured by the product of its mass and velocity.

Explanation:

Every moving object has some amount of motion and that amount of motion is known as momentum, for example if a boy is running with some velocity and certainly it has some mass as well. If we take product of his velocity with his mass or if we multiply its mass and velocity then the result obtained will be its momentum.

Formula:

Momentum = mass × velocity
P = m × v

Unit of Momentum:

kg m/s2

Newton's Law of Universal Gravitation

2015-07-13T01:30:00.000+05:00

Q. State and explain Newton's Law of Universal Gravitation:-

Introduction:

In 1687, Sir Isaac Newton stated the Law of Universal Gravitation between two bodies.

Statement:

It states that, Any two bodies in the universe attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of distance between them.

Explanation:

Law of Gravitation or Universal Gravitation says that in the whole universe there is always a force of attraction between bodies that allows them to attract each other, this force of attraction increases with the increase in mass and decreases with the decrease in distance between two bodies. This law is generally applies on heavenly bodies such as stars, moons, planets but it also apply on humans, animals and all other creatures however, due to the small mass as compared to heavenly bodies the force of attraction between creatures or humans is negligible.

Gravitational Force between two masses.

Mathematically we get:

F ∝ m1 × m2
F ∝ 1 ÷ r2

Now Combine both equations:

F ∝ m1 × m2 ÷ r2

Therefore:

F = G × m1 m2 ÷ r2

:. G is Newton's constant & value of G = 6.67 × 10-11 Nm2 /kg2

Exam cOrner PK!

7 C of Communication

The Seven C's of Communication.

Clarity:

Coherent:

Correctness:

Conciseness:

Concreteness:

Completeness:

Courteousness:

Effective Communication

Body Language:

Consideration of Listener/Audience:

Right Interpretation of the Message:

Be Brief but Specific:

What is Mole?

What is System of Forces with Practical Examples

What is System of Forces?

When two or more forces act on a body, they are called to form a system of forces.There are various systems of forces mentioned below with their day-to-day examples.

Collinear Forces:

Examples:

Co-Planar Forces:

Examples:

Concurrent Forces:

Examples:

Non-Concurrent and Co-Planar Forces:

Examples:

Concurrent and Co-Planar Forces:

Example:

What is Avogadro's number

Avogadro's Number:

Example:

Tips and tricks for scoring highest in Entry Test of any University.

Things to keep in mind for Entry Test:

Good Luck ^_^

Mole vs Molecule | Difference between mole and molecule

Impact of Internet on Youth | Essay

All about Sets

Geometry

Trigonometry

What is ALGEBRA?

Scalars and Vectors

MOTION

Q. What is Motion and its type..?

Hydrolysis and Hydration

Q. What is Hydrolysis and Hydration?

Hydrolysis:

Hydration:

Chemical Equation

Q. What is Chemical Equation?

Chemical Equation:

Types of Chemical Reactions

Q. Explain types of Chemical Reactions with example:-

1. Combustion Reaction:

2. Addition or Combination or Synthesis Reaction:

3. Decomposition Reaction:

4. Substitution or Single Displacement Reaction:

5. Double Displacement Reaction:

6.Neutralization or Acid-Base Reaction:

Chemical Reaction

Q. What is a Chemical Reaction?

Molecule

Q. What is Molecule?

Element, Compound and Mixture

Q. What is an Element?

Q. What is Compound?

Q. What is Mixture?

Mass

Atom

Law of Conservation of Momentum

Q. Explain the Law of Conservation of Momentum with the help of an example:-

Introduction:

Statement:

Explanation:

Define Momentum

Q. What is Momentum?

Definition:

Explanation:

Formula:

Unit of Momentum:

When two or more forces act on a body, they are called to form a system of forces.
There are various systems of forces mentioned below with their day-to-day examples.