Question

What is the current through the portable radio when using Nicad cells with a 1.25-V emf and 0.0400-Ω internal resistance?

a) 0.25 A
b) 0.31 A
c) 0.50 A
d) 0.63 A

Answer 1

The current through the portable radio when using Nicad cells with a 1.25-V emf and 0.0400-Ω internal resistance is approximately 0.385 A.

Step-by-step explanation:

To find the current through the portable radio, we can use Ohm's law, which states that V = I * R, where V is the voltage, I is the current, and R is the resistance. In this case, the voltage is the emf of the Nicad cells, which is 1.25 V, and the resistance is the sum of the internal resistance and the radio's resistance, which is 0.0400 Ω + 3.20 Ω = 3.24 Ω. So, using Ohm's law, we can calculate the current:

I = V / R = 1.25 V / 3.24 Ω ≈ 0.385 A

Therefore, the current through the portable radio when using Nicad cells is approximately 0.385 A.