Question

A walkman uses a current of 2.0 A and has an internal resistance of 3.0 Ω, how many 1.5V batteries are required.

Answer 1

ahh what's the formula again?

Answer 2

V = IR

Answer 3

okay so whats V = IR from what you're given? Ignore the 1.5V for now

Answer 4

Given I = 2, R = 3

Answer 5

what V do you get from that?

Answer 6

i got 6V. I think its wrong

Answer 7

no that's right, since 2 * 3 = 6
Okay so now you have 6V which is the amount of battery used by the walkman

Answer 8

So how many 1.5V batteries you need to make it equal 6V?

Answer 9

4 i think

Answer 10

there you go :) 1.5 * 4 = 6