A p.d. of 10 V is needed to make a current of 0.02 A flow through a wi

1.	A p.d. of 10 V is needed to make a current of 0.02 A flow through a wire. What p.d. is needed to make a current of 250 mA flow through the same wire ?
Answer» Solution : In first case, I = 0.02 amp, V = 10 volt V=IR 10 = 0.02 x R R = 10/0.02 = 500 ohm In second case, I = 250 x 10-3 amp, R = 500 ohm V = IR V = 250 x 10-3 x 500 V = 125 volt.

A p.d. of 10 V is needed to make a current of 0.02 A flow through a wire. What p.d. is needed to make a current of 250 mA flow through the same wire ?

Answer»

Solution :

In first case, I = 0.02 amp,

V = 10 volt

V=IR

10 = 0.02 x R

R = 10/0.02 = 500 ohm

In second case,

I = 250 x 10-3 amp,

R = 500 ohm V = IR

V = 250 x 10-3 x 500

V = 125 volt.

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A p.d. of 10 V is needed to make a current of 0.02 A flow through a wire. What p.d. is needed to make a current of 250 mA flow through the same wire ?

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