Please wait...
1800-212-7858 (Toll Free)
9:00am - 8:00pm IST all days

or

Thanks, You will receive a call shortly.
Customer Support

You are very important to us

For any content/service related issues please contact on this toll free number

022-62211530

Mon to Sat - 11 AM to 8 PM

Ask Electrical Appliances question free ×
  • CBSE×
  • Class 12 Science×
  • Physics×
  • Current Electricity×
  • Electrical Appliances×

Electrical Appliances Free Doubts and Solutions

CBSE - XII Science - Physics - Current Electricity

Why can we not use rubber to make electric wires?

Asked by kv.cyfuture 3rd September 2018, 12:58 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

To increase the range of an ammeter to n times, the value of shunt reuired is ( G = resistance of galvanometer )
 
1. G / n
2. G / n - 1
3. ( n - 1 ) / G
4. nG

Asked by rajeshtitu 17th July 2016, 8:57 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

in que 23 of ncert, why does the current i does not change when resistance is changed from R to X.
actully which current is referred to i.
thanks

Asked by anmeni11 19th October 2015, 9:31 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

The power of the  wre having potential difference 200 V across its end is 100 W.If the wire is cut into two equal parts,then what will be  the energy per sec  consumed by the wire.

Asked by kharendra 10th July 2015, 11:28 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Asked by Anita Sarraf Sathyavageeswaran 10th June 2015, 6:17 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Q- Two charges +3Q and -2Q placed at (a,0) and (4a,0) respectively. What is the flux emanating out of the sphere of radius 3a taking 0 as the origin?

Asked by Subhashree Lenka 23rd May 2015, 11:34 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Q- Four charges of same magnitude and same sign are palced at the corner of a square of side 0.1m . What is the electric field intensity at the centre of the square?

Asked by Subhashree Lenka 23rd May 2015, 11:17 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

In a meter bridge, the null point is found at a distance of 40 cm from A. If a resistance of 12Ω is connected in parallel with S, the null point occurs at 50.0 cm. from A. Determine the values of R and S.

Asked by Topperlearning User 28th April 2015, 12:54 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Write the principle of working of a potentiometer. Describe briefly, with the help of a circuit diagram, how a potentiometer is used to determine the internal resistance of a given cell.

Asked by Topperlearning User 28th April 2015, 12:45 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

In a meter bridge, the null point is found at a distance of 40 cm from A. If a resistance of 12 Ωis connected in parallel with S, the null point occurs at 50.0 cm from A. Determine the values of R and S.

Asked by Topperlearning User 28th April 2015, 11:02 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Write the principle of working of a potentiometer. Describe briefly, with the help of a circuit diagram, how a potentiometer is used to determine the internal resistance of a given cell.

Asked by Topperlearning User 28th April 2015, 10:48 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

(i) Calculate the equivalent resistance of the given electrical network between points A and B. (ii) Also calculate the current through CD and ACB if a 10 V dc source is connected between points  A and B and the value of R 2 Ω.

Asked by Topperlearning User 28th April 2015, 10:43 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Why do we prefer a potentiometer to measure the emf of a cell rather than a voltemeter ?

Asked by Topperlearning User 28th April 2015, 10:41 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

In a potentiometer experiment the balancing with a cell is at length 140 cm. On shunting the cell with a resistance of 5 Ω, the balancing length becomes 100 cm. What is the internal resistance of the cell?

Asked by Topperlearning User 28th April 2015, 10:33 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Why the emf of the driver cell in the potentiometer experiment is greater than the emf of the cell to be measured?

Asked by Topperlearning User 28th April 2015, 10:29 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

(i) Why the Wheatstone bridge method is more accurate than the other methods of measuring the resistances? (ii) When the balance point is obtained in the potentiometer the current is drawn from which battery?

Asked by Topperlearning User 28th April 2015, 10:22 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

The force on an electron in a potentiometer wire is 3.2 X 10-19 N. The length of the wire is 6 m. What is the e.m.f of the battery connected across the wire?

Asked by Topperlearning User 28th April 2015, 10:17 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

State the uses of potentiometer

Asked by Topperlearning User 28th April 2015, 10:12 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

The potential gradient along the length of uniform wire is 20 Vm-1. The length of wire is 1m. What is the potential difference across two points on the wire separated by distance 40 cm?

Asked by Topperlearning User 28th April 2015, 10:12 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

A potentiometer wire is 5 m long and a potential difference of 6 V is maintained between its ends. Find the emf of a cell which balances against a length of 180 cm of the potentiometer wire.

Asked by Topperlearning User 28th April 2015, 10:11 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

What do you mean by sensitivity of potentiometer? How can we increase the sensitivity of potentiometer?

Asked by Topperlearning User 28th April 2015, 9:58 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Why do we prefer a potentiometer of longer length for getting the accurate readings?

Asked by Topperlearning User 28th April 2015, 9:54 AM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

two galvanometer a and b requires 3ma and 6ma to produce the same deflection of 10 divisions then 
 

Asked by Mendy 13th April 2015, 1:17 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Q.What is the effect of changing the resistance of primary circuit and secondary circuit on the balancing length of a potentiometer?

Asked by Ravi consul 4th March 2015, 6:41 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

<div>Q.In series combination of power</div> <div>&nbsp; &nbsp;Let two appliances be connected in series combination with resistances R and S connected to a battery of emf E and current in the circuit be I.</div> <div>So let equivalent circuit has resistance P</div> <div>&nbsp; &nbsp; &nbsp;In series,</div> <div>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; P=R+S</div> <div>Multiplying both sides by&nbsp;<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=546d1ab7dcb516407688c767e82f3843.png" alt="I squared" align="middle" /></div> <div>SO &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=546d1ab7dcb516407688c767e82f3843.png" alt="I squared" align="middle" />P=<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=546d1ab7dcb516407688c767e82f3843.png" alt="I squared" align="middle" />R+<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=546d1ab7dcb516407688c767e82f3843.png" alt="I squared" align="middle" />S</div> <div>Hence &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;equivalent power =&nbsp;<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=cce6ebff9dba7b3e77d9c3c5fa047f69.png" alt="P subscript R" align="middle" />+<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=2ff5802dc80e3c1d43d29e26bc30258b.png" alt="P subscript S" align="middle" />. &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [power=<img class="Wirisformula" src="https://images.topperlearning.com/topper/tinymce/integration/showimage.php?formula=546d1ab7dcb516407688c767e82f3843.png" alt="I squared" align="middle" />resistance]</div> <div>what's wrong in this??????</div>

Asked by Ravi consul 4th March 2015, 6:38 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

at great distance from an electric dipole the electric field strength due to the dipole varies with distance r as (ans.1/r3) pls explain how?

Asked by Nidhi 27th December 2014, 1:37 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

Asked by Shubham Jain 22nd November 2014, 4:27 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

what are the two causes of one sided deflection in galvanometer in potentiometer experiment?how can you identify each fault ? how can you rectify them?

Asked by Shubham Jain 21st November 2014, 2:40 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

why do all appliances or devices get heatned up due to excessive?

Asked by Suhas v 4th October 2014, 6:48 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

CBSE - XII Science - Physics - Current Electricity

what is meant by a post office box? and menntion its proper uses.

Asked by Sagar krishna 16th May 2014, 7:33 PM
Answered by Expert

Answer this question

×
Your answer has been posted successfully!

Chat with us on WhatsApp