Question

if 5 A current flowing a wire develops a potential difference of 30 V on a wire of resistance 20 ohm? ​

Answer 1

Correct Question :

A current of 5 amperes flows through a wire whose ends are at a potential difference of 3 volts. Calculate the resistance of the wire.

$\rule{200}{2}$

Solution :

Current = 5 A

Potential Difference = 3 V

By Ohm's law V = IR

Then,

Put the values:

3=5R

R = 3/5 = 0.6 Ω

Answer 2

$\huge\mathtt{\underline{Solution}}$

The current is defined as rate of flow of charged particle.i.e.

i =tQ

Hence the charge flown is,

Q =i t

Hence Q =1.0×1=1C

The charge Q is due to electrons, therefore,

Q =N×e

Here Q =1C

If N is number of electrons passing and e is the electronic charge of value 1.6×10−19

Then,

N =eQ=1.6×10−191=0.625×1019electrons