When a device is used in a circuit in which the voltage is 81 v the current flowing through the device is 3 a what is the resistance of the device

= 27Ω

Explanation:

The voltage of a device =  Resistance × Current

                                         V=RI

Making R the subject of the formula we have R= V/I  

Thus resistance = Voltage/ Current

V= 81 V

I = 3 A

Using these values in the formula for resistance we can then find the resistance of the device as follows.

R = 81 V/ 3 A

= 27Ω

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