Question

The current in the wires of a circuit is 90 milliAmps. If the resistance of the circuit were doubled (with no change in voltage), then its new current would be _____ milliAmps.

Answer 1

`I = 45mA`

Step-by-step explanation:

Given

`I = 90mA` --- Current

Required

Determine the new current when resistance is doubled

Using
`V = IR`

Initially, we have:

`V = 90mA * R`

When resistance is doubled and voltage remains unaltered, we have:

`V = I* 2R`

2R represents the new resistance and I represents the new current

Equate both values of V

`90mA * R = I* 2R`

Make I the subject

`I = (90mA * R)/(2R)`

`I = (90mA )/(2)`

`I = 45mA`

The new current is 45milliAmps