Question

A calculator is rated at 0.37 W when con-

nected to 2.60 V battery.
What is the resistance of this device?

Answer 1

18.6 Ω

Step-by-step explanation:

Resistance =
`(Voltage)/(Current)`

But first we have to find the current.

Current =
`(Power)/(Voltage)`

Power = 0.37W

Voltage = 2.60V

∴ Current =
`(0.37)/(2.60)`

= 0.14 ( 3 significant figures)

Now we can find the resistance.

Resistance =
`(2.60)/(0.14)`

= 18.6 Ω ( 3 significant figures)