A p.d. of 10V is needed to make a current of 0.02A flow through a wire. What p.d. is needed to make a current of 250mA flow through the same wire?
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In first case,
I = 0.02 amp, V = 10 volt
V = IR
10 = 0.02 × R
$\text{R}=\frac{10}{0.02}=500 \ \text{ohm}$
In second case,
I = 250 × 10-3 amp, R = 500 ohm
V = IR
V = 250 × 10 - 3 × 500
V = 125 volt.
I = 0.02 amp, V = 10 volt
V = IR
10 = 0.02 × R
$\text{R}=\frac{10}{0.02}=500 \ \text{ohm}$
In second case,
I = 250 × 10-3 amp, R = 500 ohm
V = IR
V = 250 × 10 - 3 × 500
V = 125 volt.
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