Tikes Education

Picture Books Collection for Early Learning

2021-01-30T13:52:00.004+05:30

PICTURE BOOKS COLLECTION

FOR EARLY LEARNING

This book will help children in basic learning with the help of picture.

Like-

Learning in ABC (alphabet).
Numbers.
Body parts.
Flower names and so on.

FOR MORE DETAILS

What is a thyristor | Construction | Working | Advantage and disadvantage | Application

2020-09-25T11:37:00.000+05:30

INTRODUCTION-

Thyristor is unidirectional like a diode that allows flow of current only in one direction. In contrast to diode, thyristor can attenuate the forward current until its is set off by an appropriate gate signal among gate and cathode terminal.

Image source - Google | Image by - Pixabay

Thyristor is also called "SCR" (Silicon Control Rectifier) because As silicon is used for construction and it is operated as a controlled rectifier i.e very low resistance in forward direction and very high resistance in reverse direction.

Construction of Thyristor-

Thyristor is a 4 layer , 3 Junction , with substitute layers of p-type and n-type materials. it has three terminals Anode(A) terminal , cathode(K) terminal , and Gate(G) terminal.

Image source - Google | Image by - Wikimediacommmons

The terminal associated with external p-type material is called anode(A). The terminal connected to the outer n-type material is called cathode(K).Gate terminal is usually kept near the cathode terminal.

With four layers of interchange p-type and n-type materials it structures 3 intersections or junctions j1, j2 and j3.

Working-

A thyristor is a unidirectional part and takes after a diode yet with an additional terminal – gate. The purpose of the gate terminal is to enable the device to be switched from a non-conducting mode (forward blocking mode) into a low resistance, conducting state (forward conducting mode). When it has been turned on by the gate terminal, the gadget remains hooked in the on-state. Which means it doesn't require persistent gracefully of gate current to stay in conduction. However the anode remains emphatically one-sided, it can't be turned off until the anode current falls beneath the holding current.

If thyristor is connected to a DC source, there is no flow of current until the gate is triggered.

(OR)

I would associate the thyristor as a switch between a battery and a light, nothing occurs until the gate is set off.Then the lamp is switched on.However - there is no off-switch. The best way to turn it off, is to eliminate battery power.

Application-

Thyristors are utilized in engine speed controls, light dimmers, pressure-control frameworks, and fluid level controllers.

Advantages-

1) The SCR (silicon controlled rectifier) can deal with large voltage, current and power.

2) The Triggering circuit for silicon controlled rectifier (SCR) is straightforward. The SCR is not difficult to turn ON.

3) The SCR can be secured with the assistance of wire.

4) It can control AC power.

5) It is easy to control.

6) It cost is low.

Disadvantages-

1) The SCR (silicon controlled rectifier) is unidirectional gadgets, so it can control power just in DC power during positive half pattern of AC signal, in this manner just DC power is controlled with the assistance of SCR.

2) The gate current can't be negative.

3)In AC circuit, it ought to be turned on each cycle.

4)It can't be utilized at higher frequencies.

What is 555 timer (part-2)

2020-09-21T07:17:00.000+05:30

Function of 555 timer-

So, by this threshold voltage, we are controllingthe output voltage. And same is true with this trigger pin. So, let's say, the voltage at this threshold pin is less than (2/3)Vcc voltage. That means the output of the first comparator is low voltage. Now, whenever this trigger signal goes below this (1/3)Vcc voltage, then the output of the second comparator will become high. So, in this case, S will become 1 and R willbe equal to zero. So, this flip-flop will get set to the logic1. And in a way, the output will also get set to the logic 1.

Image Source - Google | Image by - wikimediacommmons

So, using these threshold and trigger pins actually we are controlling the output voltage. And in a way, we are controlling the timing of this output signal. So, to change the input voltage to this threshold pin, the external resistor and the capacitors are connected between this threshold and the discharge pin through the supply voltage. And the same is true with the trigger signal. Then there is one more pin, using which wecan also control the timing. And that pin is the pin number 5. Thus, this pin is known as the control pin. And it is directly connected to the inverting terminal of the first comparator.

Now, if you see the inverting terminal of this first comparator, there is a reference voltage of (2/3)Vcc applied using this voltage divider circuit. So, by default, the reference voltage to the first comparator is (2/3) Vcc. But it may, utilizing this control pin, we can externally apply some other reference voltage and by which we can change the circumstance of the output signal.So, using this control, threshold and thetrigger pins, we can change the timing of the output signal. Now, as I said before to change the inp[utat this threshold pin, the external resistor and the capacitors are connected between this threshold and the discharge pins. Along these lines, this release pin helps the capacitor in the releasing at whatever point the output is in a low state. So, let's understand how this transistor will help the capacitor in the discharging. So, let's say the output of this 555 timeris 0V. It means that the Q-bar signal will be equalto 1. Because here this output drive circuit isthe inverting circuit.

So, as this Q-bar is 1, the base of this transistor will be at high voltage. So, here this transistor acts like a switch. So, whenever the input to this transistor is logic 1, then it will act as a closed switch. What's more, it will offer an exceptionally low impedance to this capacitor. So, through this path, the capacitor willget discharged. On the other end, whenever this Q-bar is zero,or let's say the output is high, at that time the input to this transistor will be equal to zero. thus, this transistor will go about as an open switch.So, in that case, this transistor will provide a high impedance to this capacitor. And the last pin which is retained is the reset pin. Presently, this reset pin is a functioning low pin. It means that when logic 0 is applied to this pin, then the flip-flop of this 555 timer will get reset.

Image source - Google | image by - Wikimediacommons

Furthermore, as it were, we can say that the output of the 555 timer will likewise get reset.So, irrespective of the working of this 555timer, whenever this reset pin goes low, the output of this 555 timer will become zerovolts. Or we can say that the 555 timer will get reset. Thus, at whatever point this pin isn't in an utilization then it ought to be associated with the supply voltage. So, in this way, in this 555 timer ic, by changing the inputs we can control the timing of the output signal and by connecting the external components like a resistor and the capacitor this 555 timer can be configured either as astable, monostable and bistable multivibrator. So, in the future videos, we will see that by connecting the external components how this 555 timer can be configured either as astable, monostable and the bistable multivibrator.

What is 555 timer (part-1)

2020-09-18T08:33:00.000+05:30

Introduction to 555 timer -

555 timer ic is extremely mainstream ic and it is helpful in the circumstance related applications. Presently, this 555 timer ic is accessible in endless bundles. But here we are going to talk about the 8pin DIP package.

Image source - Google | image by - snappyGoat

Pin Diagram-

if you see the pin diagram, then the pin diagram will look like this. And here is the corresponding name of each pin. Along these lines, we should quickly observe the depiction of eachpin and how about we additionally observe the inside square chart of this 555 timer.So, this is the internal block diagram ofthis 555 timer ic.The first one is the voltage divider circuit. Then the next block is the comparators. And if you see, the output of the comparatoris going to the flip-flop circuit. The flip-flop is the third block.

Image Source - Google | Image by - wikimediacommmons

there is a discharge circuit for the discharging purpose. And then after the last block is the outputdriver circuit. So, these are the basic blocks of this 555timer ic.In this way, individually we will see the capacity ofeach block.And at the same time, we will also understandthe purpose of individual pins.Presently, here the reason for this pin number 1,3 and 8 is quite direct.So, let's first of all talk about these threepins. so, in this 555 timer ic, the pin number 8is the supply voltage pin. And usually, the supply voltage in the rangeof 4.5 to 15V is applied at this pin. And the pin number 1 is the ground pin. And it is connected to the circuit ground. then if you see the third pin, the pin number3 is the output pin.

so, this pin is capable of driving the TTLloads and it can source or sink up to the 200 mA of current. Now, to understand the purpose of the restof the pins, first of all, let's understand the working of each block. So, as I said, the first block of this 555timer ic is the voltage divider circuit. Now, if you see over here, the voltages attwo nodes are going to the comparator.Further more, here we are accepting that the operation-amp which is utilized as a comparator is an ideal operation-amp. So, no current is flowing into the op-ampterminals. So, we can say that from this supply voltage,the current is flowing only through these three resistors.Also, that is the reason we can straightforwardly apply the voltagedivider rule.

So, by applying the rule we can say that thevoltage at this node will be equal to 2R*Vcc/(2R+R). Or we can say that the voltage at this nodeis equal to (2/3)Vcc. And this voltage is given as a reference tothis first comparator.So also, the voltage at this node can befound utilizing the voltage divider rule.So, the voltage at this node will be equalto R*Vcc/(R+2R) Or we can say that it is equal to (1/3) Vcc.Now, if you see over here, the other two pinswhich are going to this comparator is threshold and trigger pins. So, these two pins are the input pins. And by changing the voltage at these two pins,we can change the output of this comparator. So, if you see over here, the inverting nodeof this first comparator is at the 2/3 Vcc voltage. So, whenever this threshold voltage goes abovethis (2/3)Vcc voltage then, the output of the comparator will become high voltage. And similarly, if we talk about this secondcomparator, then whenever this trigger input goes below this (1/3)Vcc voltage, at thattime output of this second comparator will become high voltage.

So usually, this trigger voltage used to beat the supply voltage and whenever we want to change the state of the comparator, thenthe trigger signal is changed in a such a way that the output at this pin number 2 goes below this (1/3) Vcc voltage. Now, let's see whenever the output of this, changes then how it affects the other circuitry. So, if you see, the output of this comparatoris given to the flip-flop circuit. So, if you observe over here, the used flip-flopin the 555 timer ic is the RS flip-flop. So, let's see the truth table of this R-Sflip-flop. Now, as this R-S flip-flop is a digital circuit,so we are considering the input voltage to the flip-flop as either logic 1 or logic 0.

Image source - Google | image by - Wikimediacommons

So from the truth table as you can see, wheneverboth inputs are logic 0 then the output of this flip-flop will be the same as the previousstate. It means that before applying this two inputs,if previously the output is either 0 or 1, then after applying these two inputs the outputwill remain the same. On the other hand, if the input to this S-Rflip-flop is 0 and 1 respectively, at that time irrespective of the previous output theflip-flop will get reset to the logic 0. And likewise, whenever S is 1 and R is 0,then irrespective the previous state of the flip-flop, the flip-flop will get set to thelogic 1. And whenever both inputs are logic '1' at that time the output is undefined.In this way, here we are just intrigued by these two conditions.So, for a moment let's assume that this triggersignal is at Vcc voltage. It means that the output of the second comparatoris at logic 0. Or we can say that, this S=0.Presently, at first we should accept that this threshold voltage is not as much as this reference voltage, that is (2/3) Vcc. And at that time, the output of this firstcomparator will be also equal to 0. So, in this case, the output of the flip-flopwill remain as it is Now, whenever this threshold voltage goes above this (2/3)Vcc voltage,then the output of the first comparator will become logic 1. Along these lines, around then the output of the flip-flop will be equivalent to 0. In this way, independent of the past state, now the output of the flip-flop is zero.And because of that, the output of this 555timer will also become zero.

CODING-DECODING

2020-06-01T20:29:00.000+05:30

' CODING-DECODING '

CODE is an appointment of giving an indication and DECODING may be a technique to translate the CODE.

Coding-decoding reasoning

The Coding and Decoding Test is remember for a few serious tests in light of the actual fact that to pass judgment on an up-and-comer's capacity to translate the code language. While taking care of the problems on CODING-DECODING, English people letter set and their number worth helps the up-and-comers execution.

A - 1 ,
B - 2,
C - 3 ,
D - 4,
E - 5,
F - 6,
G -7,
H - 8,
I - 9,
J - 10,
K -11,
L - 12,
M -13,
N- 14,
O - 15,
P - 16,
Q - 17,
R - 18,
S - 19,
T - 20,
U - 21,
V - 22,
W - 23,
X - 24,
Y - 25,
Z -26.

There are some instances of coding and Decoding -

Model 1. On the off chance that GIVE is coded as 5137 and BAT is coded as 924 , how is Door coded ?

5427 (b) 2547 (c) 5247 (d) 5724

Sol: Clearly it fine is also seen that G is coded
as 5 ; An as 2 , T as 4 , and E as 7 . So
that GATE is 5247. the correct answer
is (c).

Model 2. in a very specific code, 15789 consists as XTZAL and 2346 consists as NPSU. How is 23549 written therein code?

NPTUL (b) PNTSL (c) NPTSL (d) None of them

Sol: it's certain that 2 is coded as N , 3 as P, 5 as T, 4 as S, and 9 as L. Thus, 23549 is coded as NPTSL. the acceptable response is (c) .
_____________________________________________

* TRICK to seek out OPPOSITE LETTER'S :-

The 2 letters of English Alphabet which total is 27, they're OPPOSITE letters of 1 another.

Model - C = 3, X = 24 》C + X = 3+24 = 27.

Model 3. On the off chance that in a very specific code language ABCD consists as ZYXW, at that time how is that the word DANCE written therein code?

WZMXV (b) MXZWV (c) VMZXM (d) ZMWXV

Sol : An is that the principal letter from the start of letter set which is coded as first letter from the top as an example Z, etc.

》DANCE is coded as WZMXV. the acceptable response is (a).

Model 4. in a very specific code language, '479' signifies 'fruit is sweet ' ; '248' signifies 'very sweet voice ' and '637' signifies ' eat fruit daily ' . Which digit means 'is' therein code?

(a) 7 (b) 9 (c) 4 (d) cannot be resolved

Sol: within the first and second articulation, the conventional code digit is '4' and regular word is 'sweet ' so '4' signifies 'sweet ' correspondingly from first and third proclamation, we locate that '7' signifies 'fruit ' .Thus within the subsequent explanation, '9' signifies 'is' .So the appropriate response is (b).

Practice Questions :-

Important questions

Q1. in a very specific code, MENTION consists as LNEITNO . How is PATTERN written therein code?

(an) APTTREM (b) PTAETNR (c) OTAETNR (d) OTAETRN

Q2. within the event that PAINT is coded as 74128 and EXCEL is coded as 93596, at that time how might you interpret ACCEPT ?

(a) 455978 (b) 547978 (c) 554978 (d) 735961

Q3. within the event that finger is named toe, toe is named foot, foot is named thumb, thumb is named lower leg, lower leg is named palm, palm is named knee, which one finger has diverse name?

Thumb (b) Ankle (c) Knee (d) Palm

Q4. in a very specific code language '526' signifies 'sky is blue ' ; '24' signifies 'blue colour ' and '436' signifies 'colour is fun ' . Which of the accompanying digit means 'fun' ?

(a) 5 (b) 4 (c) 3 (d) 2

*if you've got any issues to tackling these above inquiries please get in contact with me or remark within the Comment area.

Introduction ' TIKES EDUCATION '

2020-05-23T12:02:00.001+05:30

Hi,

I'm tikes kumar.

This is an educational blog.

There are some important topics for students with be cover in this blog.

Thanks.