Question

The current l, in a circuit varies inversely with the resistance, R. If the resistance is 12 when the current is 3, what is the resistance when the current is 6?

Answer 1

6

Explanation:

Given I varies inversely with R then the equation relating them is

I =
`(k)/(R)` ← k is the constant of variation

To find k use the condition R = 12 when I = 3

k = IR = 3 × 12 = 36

I =
`(36)/(R)` ← equation of variation

When I = 6, then

6 =
`(36)/(R)`, hence

R =
`(36)/(6)` = 6