Question

A 0.2 mm radius gold wire carries a 10 A current.

Calculate:-The electric field in the wire.-

The potential difference between two points in the wire 5 m apart.-

The resistance of 5m length of this wire

Answer 1

SOLUTION:

r = radius of wire = 0.2 mm= 0.2*10^-3 m

I= 10 A = current

A= area of wire

= resistivity of wire

a) the electric field =E

the electric field is = 1.94 V/m

b) L= 5 m

the potential different between two point in the wire apart from 5 m is =V

V=E*L

THE potential different is = 9.71V

c)

the resistance = R

the resistance is =