MATHEMATICAL LOGIC

Nuclear Fusing with Lasers

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 18 Oct 2023 13:02:00 +0000

Fusion is a process in which atoms of two elements are compressed to such an extent that their nuclei fuse together and a new element is produced, whose mass is less than the sum of the masses of the two elements. The difference in mass is converted into energy in accordance with Einstein's equation E = mc².

For example, if one gram of mass is converted into energy, 9×10¹¹ Joules of energy will be released, which is equal to the energy generated by 1000 MW power station run continuously for 25 hours. The enormous amount of energy released from the sun is due to fusion of hydrogen brought about by gravitational forces. The sun produces energy of the order of 3×10²⁶ Joules/sec.

Fusion also is a source of energy in stars. The potential of controlled thermonuclear fusion, as an inexhaustible source of energy, is now well established.

For the nuclei to fuse together a way must be found to overcome the mutual electrostatic repulsion or Coulomb repulsive barrier between the proton clouds of the two nuclei. This could be done by heating the matter to such a high temperature (~10 K) that the thermal velocity imparted to the nuclei is sufficient to overcome the mutual electrostatic repulsion. Matter at such high temperature comprises a mixture of electrons and ions (i.e.,) a plasma.

The fusion power released at such a high temperature is much greater than the energy lost by radiation. However, for the release of a sufficient amount of thermonuclear energy and to sustain fusion reaction, it is necessary to confine the hot plasma, so that the fusion reaction continues for a long time. The laser has the potential to generate very high temperature and pressure required to initiate a fusion reaction and to concentrate large amount of energy in a small volume and hence, can be an extremely useful tool in bringing about a fusion reaction.

In a typical scheme, a pea-sized target pellet, a fraction of a millimetre in diameter containing fusion fuel - usually a deuterium-tritium mixture- is projected into a reaction chamber, where it is suddenly irradiated with intense, high-energy laser beam. A pulse of 1ns duration develops a power density of ~10¹⁶ cm² at the pellet surface. As the surface of the target blasts away, the rocket like reaction forces implode the target's interior to densities (~1,000 times liquid density) and temperature (~100,000,000°C) sufficient to cause the nuclei to fuse, releasing a large amount of thermonuclear energy in accordance with the equation

D + T ⟶ 4He + n + 17.6 MeV

, where n represents a neutron.

For both inertial and magnetic fusion, burn efficiency (i.e.,) the percentage of nuclei that fuse is proportional to the product of density and confinement time. In magnetic fusion, the fuel density is limited by material properties, so the efficiency of the burn is increased by extending the duration of confinement. In inertial fusion, Newton's laws and thermal velocity limit the confinement time, so the fuel is compressed to higher densities.

Periodic and Oscillatory Motions:

noreply@blogger.com (MATHEMATICAL LOGIC) — Tue, 01 Mar 2022 00:09:00 +0000

Periodic Motion:

Periodic motion is the motion that reaches the same position after an equal interval of time. That is it repeats the motion along the same path having a fixed time interval.

Examples:

1) Revolution of the planets around the Sun,

2) The motion of the wheel of the car, and

3) The motion of the hands of the clock.

These are examples of periodic motion.

Oscillatory Motion:

Oscillatory motion is the back and fro motion about a mean position.

Examples:

1) The motion of the pendulum,

2) The motion of the bouncing ball, and

3) The motion of the tuning fork undergoes vibration.

These are examples of oscillatory motion.

Conclusion:

The periodic motion either be oscillatory or be non-oscillatory. But an oscillatory motion is always a periodic motion.

For example, the revolution of the planets around the Sun is periodic but not oscillatory. The motion of the pendulum is either periodic or oscillatory.

All oscillatory motion can be periodic but all periodic motion cannot be oscillatory.

Simple Harmonic Motion:

Simple Harmonic Motion (SHM) is a special type of oscillatory periodic motion in which a particle undergoes displacement equally on both sides of the equilibrium point because of restoring force.

The restoring force is a kind of force which always directed towards the equilibrium point.

The equation of a simple harmonic motion is given by,

y = A sin(kx + ωt + ɸ),

where ω is the angular velocity, k is the wave vector, A is the amplitude and ɸ is the phase. The frequency of a simple harmonic motion is independent of the amplitude.

The characteristics of a simple harmonic motion:

The characteristics of a simple harmonic motion are,

1.) Simple Harmonic Motion is always periodic in nature. This is the characteristics of a periodic wave.

2.) The acceleration of the restoring force is directly proportional to the displacement of the wave. This is the characteristics of an oscillatory wave.

3.) The acceleration of the restoring force is directed towards the equilibrium point which is the mean position. This is the characteristics of an oscillatory wave.

4.) In simple harmonic motion, the total energy is conserved.

5.) The periodic functions like a sine wave or cosine wave (i.e., sinusoidal wave) can be used to represent the simple harmonic motion.

Kepler's laws and their Applications :

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 13 Oct 2021 05:36:00 +0000

Kepler's laws and their Applications :

Definition:

Kepler's laws which explain the motion of the planets can be defined as follows:

Kepler's first law can be defined as all planets orbiting about the Sun in an elliptical path, and the Sun is presenting in the focus of their elliptical path.
Kepler’s second law can be defined as a line segment that, joining any planet of our solar system to the Sun, covers the equivalent regions in equivalent time.
Kepler’s third law can be defined that the orbital periods of revolving planets having power of two are directly proportional to their distances from the Sun having power of three.

Kepler's laws are the most important law of planetary motions of our Solar system. These laws were derived and inferred by Johannes Kepler. He didn't either number these laws or separated them extraordinarily from his different revelations by himself. Kepler confirmed that the planets of the solar system are orbiting in elliptical paths which is Kepler’s first law. Kepler’s second law confirmed that a planet is orbiting the Sun in an elliptical path, when it comes nearer to the Sun, it travels quicker. Kepler's third law confirmed that the farthest planet is having a slower orbital speed.

Applications of Kepler's law are as follows :

Kepler's law is used to predict the paths of astronomical objects of our solar system such as comets and asteroids, and also the orbits of the artificial satellites. Kepler's first law is used to conclude the shape of the path of planets of our solar system. Kepler's second law is used to confirm the correct orbit from several possible orbits for double star's orbit. Double stars are the pair of stars that appear nearer to each other if viewed from the Earth. Kepler's third law is used to confirm that the orbital period of the planets and the objects orbiting the Sun other than planets also increases when the radius of the solar bodies increases.

Kepler's laws are as follows :

Kepler's first law : All planets orbiting about the Sun in an elliptical path, and the Sun is presenting in the focus of their elliptical path.
Kepler’s second law : A line segment that, joining any planet of our solar system to the Sun, covers the equivalent regions in equivalent time.
Kepler’s third law : The orbital periods of revolving planets having power of two are directly proportional to their distances from the Sun having power of three.

Applications of Kepler's law are as follows :

To predict the paths of astronomical objects of our solar system.
Kepler's first law : To conclude the shape of the path of planets of our solar system.
Kepler's second law : To confirm the correct orbit from several possible orbits for double star's orbit.
Kepler's third law : To confirm that the orbital period of the solar bodies increases when the radius of the solar bodies increases.

Dual Nature of Light

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 06 Sep 2021 11:50:00 +0000

Dual Nature of Light

Definition:

The dual nature of light can be defined as that the light can interact like a particle as well as a wave. When light interacts like a particle, it travels in straight lines.

When light interacts like a wave, it undergoes diffraction and interference.

Diffraction means bending of the waves happens around the edges of the obstacles.

From Thomas Young’s double-slit interference experiment, we can declare that light can interact like a particle. In Young's double-slit interference experiment, the light is passed through a double-slit. The light coming from two different slits either gets added together or gets canceled each other. Then, it forms the interference fringes. This phenomenon (interference) is possible only if the light interacts like a wave. When the crust or trough of the two waves interacts gets added and the crust and trough of the two waves interact cancel each other.

Louis de Broglie stated that the moving particle can have the properties of a wave whatever its nature. According to de Broglie, the wavelength of the moving particle is directly proportional to Planck's constant and inversely proportional to the momentum of the particle. The waves associated with the particles are called de Broglie waves or matter waves.

Davisson and Germer’s study of the experiment of matter waves gave evidence to the hypothesis of de Broglie that a moving particle can have a wave nature. The wavelength of the diffracted electron which was calculated based on Davisson and Germer’s experiment is in good agreement with the wavelength of the wave which was calculated using de Broglie's hypothesis.

Einstein declared that light behaves like a particle called a photon. The photoelectric effect verifies that light exhibits particle nature and also has quanta of energy which is called the photon. The photon is a massless particle having energy and momentum and travels with the speed of light. This particle-like nature of light is proved by Compton scattering of X-rays. Compton scattering of X-rays can be treated as a particle collision experiment between an X-ray photon and an electron that is loosely bound. The Compton effect was explained by the quantum theory of radiation.

Light can interact like a particle (i.e., photon) as well as a wave.
When a light behaves like a particle, it moves in straight lines. The particle nature of light is confirmed by the photoelectric effect and Compton scattering of X-rays.
When a light behaves like a wave, it undergoes diffraction and interference. The wave nature of light is confirmed by Thomas Young’s double-slit interference experiment and the study of experimentation of matter waves by Davisson and Germer.

NET JRF PART - A : Questions and Solutions : NET JUNE-2019

noreply@blogger.com (MATHEMATICAL LOGIC) — Sun, 27 Sep 2020 00:16:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2019

For Similar Questions click here

1.) How many quadrilaterals does the following figure have?

(a) 17

(b) 18

(d) 20

Ans.: (c) 19 .

Solution:

The quadrilaterals formed are :

The total number of quadrilaterals formed are 19.

____________________________________

For Similar Questions click here

NET JRF PART - A : Questions and Solutions : NET JUNE-2013

noreply@blogger.com (MATHEMATICAL LOGIC) — Tue, 22 Sep 2020 07:26:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2013

1.) Choose the largest number:

(a) 2⁵⁰⁰ (b) 3⁴⁰⁰ (c) 4³⁰⁰ (d) 5²⁰⁰

Ans. : (b) 3⁴⁰⁰ .

Solution:

2⁵⁰⁰ = ( 2⁵ )¹⁰⁰ = 32¹⁰⁰ .

3⁴⁰⁰ = ( 3⁴ )¹⁰⁰ = 81¹⁰⁰ .

4³⁰⁰ = ( 4³ )¹⁰⁰ = 64¹⁰⁰ .

5²⁰⁰ = ( 5² )¹⁰⁰ = 25¹⁰⁰ .

Thus, we see that out of the given numbers 3⁴⁰⁰ is the largest .

NET JRF PART - A : Questions and Solutions : NET JUNE-2014

noreply@blogger.com (MATHEMATICAL LOGIC) — Tue, 22 Sep 2020 07:26:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2014

1.) Suppose

x∆y = ( x - y )² ;

xoy = ( x + y )² ;

x*y = ( x × y )^-1 ;

x•y = x × y ;

+, – and × have their usual meanings. What is the value of { ( 197o315 ) - ( 197∆315 ) } • ( 197*315 ) ?

(a) 118 (b) 512 (c) 2 (d) 4

Ans. : (d) 4 .

Solution:

{ ( 197o315 ) - ( 197∆315 ) } • ( 197*315 )

= { ( 197 + 315 )² - ( 197 - 315 )² } • ( 197 × 315 )^-1

= { ( 197 + 315 + 197 - 315 ) ( 197 + 315 - ( 197 - 315 ) ) } • 1 / ( 197 × 315 )

= { ( 197 + 315 + 197 - 315 ) ( 197 + 315 - 197 + 315 ) ) } • 1 / ( 197 × 315 )

= { 394 × 630 } •1 / ( 197 × 315 ) = 4 .

Thus,

{ ( 197o315 ) - ( 197∆315 ) } • ( 197*315 ) = 4 .

NET JRF PART - A : Questions and Solutions : NET DEC-2012

noreply@blogger.com (MATHEMATICAL LOGIC) — Tue, 22 Sep 2020 07:26:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2012

1.) Find the missing letter :

(a) H

(b) L

(d) Y

Ans.: (c) Z .

Solution:

Letters are arranged as,

So, the required letter is ( 22 + 4 ) letter of English alphabet (i.e.,) Z .

Differentiation

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:47:00 +0000

Differentiation:

1.) Differentiate the following with respect to x.

If y = 1/x√x , find dy/dx .

Solution:

Represent y in the form of a power. ( i.e., ) y = x^−3/2 .

Then dy/dx = ( −3/2 )x^{( −3/2 − 1 )}

= −3x^−5/2/2 .

dy/dx = −3x^−5/2/2 .

Differentiation

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:46:00 +0000

Differentiation:

1.) Differentiate the following with respect to x.

Find y′ if y = x² + cosx .

Solution:

We have y = x² + cosx .

Therefore,

y′ = dy/dx = d/dx ( x² + cosx )

y′ = d/dx( x² ) + d/dx( cosx )

y′ = 2x^{( 2 − 1 )} + ( − sin x )

y′ = 2x − sin x .

y′ = dy/dx = 2x − sin x .

NET JRF PART - A : Questions and Solutions : NET DEC-2012

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:45:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2012

1.) What is the next number in this "see and tell " sequence ?

1 11 21 1211 111221 _____ .

a.) 312211

b.) 1112221

c.) 1112222

d.) 1112131

Ans. : (a) 312211 .

Solution:

1 is read off as " one 1 " or 11.
11 is read off as " two 1s " or 21.
21 is read off as " one 2, then one 1 " or 1211.
1211 is read off as " one 1, one 2, then two 1s " or 111221.
111221 is read off as " three 1s, two 2s, then one 1 " or 312211.

NET JRF PART - A : Questions and Solutions : NET DEC-2012

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:44:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2012

1.) 25% of 25% of a quantity is x% of the quantity where x is :

a.) 6.25%

b.) 12.5%

c.) 25%

d.) 50%

Ans. : (a) 6.25% .

Solution:

25% of 25% = x%

25/100 × 25/100 = x%

625/10000 = x%

0.0625 = x%

6.25/100 = x%

6.25% = x%

6.25 = x

x = 6.25 .

Algebra

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:36:00 +0000

Algebra:

1.) Consider the following equation

x² + 4y² + 9z² = 14x + 28y + 42z - 147

where x, y and z are real numbers. Then the value of x + 2y + 3z is :

a.) 7

b.) 14

c.) 21

d.) not unique

Ans. : (c) 21 .

Solution:

x² + 4y² + 9z² = 14x + 28y + 42z - 147

x² + 4y² + 9z² - 14x - 28y - 42z + 147 = 0

x² + 4y² + 9z² - 14x - 28y - 42z + 49 + 49 + 49 = 0

x² - 14x + 49 + 4y² - 28y + 49 + 9z² - 42z + 49 = 0

( x² - 14x + 49 ) + ( 4y² - 28y + 49 ) + ( 9z² - 42z + 49 ) = 0

( x - 7 )² + ( 2y - 7 )² + ( 3z - 7 )² = 0

Thus, each term must be separately zero.

( x - 7 )² = 0

Take square root on both sides,

( x - 7 ) = 0

x - 7 = 0

x = 0 + 7

x = 7

( 2y - 7 )² = 0

Take square root on both sides,

( 2y - 7 ) = 0

2y - 7 = 0

2y = 0 + 7

2y = 7

y = 7/2

( 3z - 7 )² = 0

Take square root on both sides,

( 3z - 7 ) = 0

3z - 7 = 0

3z = 0 + 7

3z = 7

z = 7/3

x + 2y + 3z = 7 + 2 ( 7/2 ) + 3 ( 7/3 ) = 7 + 7 + 7 = 21 .

Then, the value of x + 2y + 3z is 21 .

Differentiation

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:36:00 +0000

Differentiation:

Differentiate the following with respect to x.

1.) If y = √x find dy/dx .

Solution:

y = √x

Let us represent this function in the form of a power,

y = x^1/2

dy/dx = ( 1/2 )x^{[ ( 1/2 ) - 1 ]}

dy/dx = ( 1/2 )x^{( -1/2 )}

dy/dx = 1/2x^1/2

dy/dx = 1/2√x .

NET JRF PART - A : Questions and Solutions : NET DEC-2012

noreply@blogger.com (MATHEMATICAL LOGIC) — Mon, 21 Sep 2020 14:36:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2012

1.) Which is the least among the following ?

0.33^0.33 , 0.44^0.44 , π^-1/π , e^-1/e

a.) 0.33^0.33

b.) 0.44^0.44

c.) π^-1/π

d.) e^-1/e

Ans. : (d) e^-1/e .

Solution:

0.33^0.33 = 0.69360082359 .

0.44^0.44 = 0.69681770628 .

π^-1/π = 3.14159265359^{-0.31830988618} = 0.69462799225 .

e^-1/e = 2.71828182846^{-0.36787944117} = 0.69220062755 .

NET JRF PART - A : Questions and Solutions : NET JUNE-2012

noreply@blogger.com (MATHEMATICAL LOGIC) — Sun, 13 Sep 2020 11:04:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2012

For Similar Questions click here

1.) How many squares are there in this figure?

(a) 9

(b) 14

(d) 17

Ans.: (c) 15 .

Solution:

The squares formed are :

The total number of squares formed are 15 .

_________________________________________

For Similar Questions click here

NET JRF PART - A : Questions and Solutions : NET DEC-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Sat, 01 Aug 2020 18:09:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2018

1.) What is the value of 1² - 2² + 3² - 4² + 5² - ....... + 17² - 18² + 19² ?

(a) -5 (b) 12 (c) 95 (d) 190

Ans. : (d) 190 .

Solution:

S = 1² - 2² + 3² - 4² + 5² - 6² + ....... + 17² - 18² + 19² .

S = ( 1² - 2² ) + ( 3² - 4² ) + ( 5² - 6² ) + ....... + ( 17² - 18² ) + 19² .

S = ( 1 + 2 ) ( 1 - 2 ) + ( 3 + 4 ) ( 3 - 4 ) + ( 5 + 6 ) ( 5 - 6 ) + ( 7 + 8 ) ( 7 - 8 ) + ( 9 + 10 ) ( 9 - 10 ) + ( 11 + 12 ) ( 11 - 12 ) + ( 13 + 14 ) ( 13 - 14 ) + ( 15 + 16 ) ( 15 - 16 ) + ( 17 + 18 ) ( 17 - 18 ) + 19² .

S = ( 3 ) ( -1 ) + ( 7 ) ( -1 ) + ( 11 ) ( -1 ) + ( 15 ) ( -1 ) + ( 19 ) ( -1 ) + ( 23 ) ( -1 ) + ( 27 ) ( -1 ) + ( 31 ) ( -1 ) + ( 35 ) ( -1 ) + 19² .

S = ( -1 ) [ 3 + 7 + 11 + 15 + 19 + 23 + 27 + 31 + 35 ] + 19² .

S = ( -1 ) [ 171 ] + 19² .

S = -171 + 19 × 19 .

S = -171 + 361 = 190 .

S = 190 .

NET JRF PART - A : Questions and Solutions : NET DEC-2015

noreply@blogger.com (MATHEMATICAL LOGIC) — Fri, 31 Jul 2020 16:59:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2015

1.) The number of squares in the figure is

(a) 30

(b) 29

(d) 20

Ans. : (b) 29 .

Solution:

1 × 1 :-

2 × 2 :-

Hence, number of squares = 29 .

NET JRF PART - A : Questions and Solutions : NET DEC-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 29 Jul 2020 17:54:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2018

1.) The curves of y = 2x² and y = 4x intersect each other at

(a) only one point

(b) exactly two points

(d) no point at all

Ans. : (b) exactly two points .

Solution:

At the point of intersections,

2x² = 4x

2x² - 4x = 0

2x( x - 2 ) = 0

Thus, x = 0; x = 2;

so, two points of Intersections.

NET JRF PART - A : Questions and Solutions : NET DEC-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 29 Jul 2020 15:42:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2018

1.) If ‘SELDOON’ means ‘NOODLES’ then what does ‘SPUOS’ mean?

(a) SALAD (b) SOUPS (c) RASAM (d) ONION

Ans. : (b) SOUPS .

Solution:

Interchanging first alphabet with last one, we get NOODLES from SELDOON.

Similarly,

NET JRF PART - A : Questions and Solutions : NET DEC-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 29 Jul 2020 10:04:00 +0000

NET JRF PART - A : Questions and Solutions:

NET DEC-2018

1.) If D = ABC + BCA + CAB, where A, B and C are decimal digits, then D is divisible by

(a) 37 and 29

(b) 37 but not 29

(d) neither 29 nor 37

Ans. : (b) 37 but not 29 .

Solution:

D = ( 100A + 10B + C ) + ( 100B + 10C + A ) + ( 100C + 10A + B ) = 111A + 111B + 111C = 111( A + B + C ) = 37 × 3( A + B + C ) .

D = 37 × 3( A + B + C ) .

NET JRF PART - A : Questions and Solutions : NET JUNE-2016

noreply@blogger.com (MATHEMATICAL LOGIC) — Wed, 29 Jul 2020 09:02:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2016

1.) What comes next in the sequence?

(a)

(b)

(c)

(d)

Ans. : (c)

Solution:

Each figure is half of alphabets starting from A . Thus, the next figure will be half of E .

NET JRF PART - A : Questions and Solutions : NET JUNE-2013

noreply@blogger.com (MATHEMATICAL LOGIC) — Tue, 28 Jul 2020 18:20:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2013

1.) How many rectangles (which are not squares) are there in the following figure?

(a) 56

(b) 70

(d) 100

Ans. : (b) 70 .

Solution:

For n × n , total number of possible rectangles :

Hence for 4 × 4 ,

= [ 4 × ( 4 + 1 )/2 ]²

= [ 4 × 5/2 ]²

= [ 2 × 5 ]²

= 10² = 100 .

For 4 × 4 , total number of possible rectangles = 100 .

For n × n , total number of squares :

Hence for 4 × 4 ,

= 4 × ( 4 + 1 ) ( 2 × 4 + 1 )/6

= 4 × 5 × ( 8 + 1 )/6

= 4 × 5 × 9/6 = 30 .

For 4 × 4 , total number of squares = 30 .

Hence, number of rectangles ( not squares ) = 100 - 30 = 70 .

NET JRF PART - A : Questions and Solutions : NET JUNE-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Sun, 26 Jul 2020 19:01:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2018

1.) In a sequence of 24 positive integers, the product of any two consecutive integer is 24 . If the 17th member of the sequence is 6 , the 7th member is

(a) 24 (b) 4 (c) 6 (d) 17

Ans. : (c) 6 .

Solution:

The only possible numbers of the sequence can be those integers which are divisors of 24 . Thus 1, 2, 3, 4, 6, 8, 12 and 24 can be members of the series. From the question the 17th member will be 6 hence 16th and 18th member will be 4 . Using the same reasoning we see that the sequence is

6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4, 6, 4,.....

Hence, we conclude that the 7th member of the series is 6 .

NET JRF PART - A : Questions and Solutions : NET JUNE-2018

noreply@blogger.com (MATHEMATICAL LOGIC) — Sun, 26 Jul 2020 18:03:00 +0000

NET JRF PART - A : Questions and Solutions:

NET JUNE-2018

1.) Which of the following be the correct pattern in the empty square?

(a)

(b)

(c)

(d)

Ans. : (c)