Question

Which of the following represents the power generated in an electric bulb having a filament of resistance 2R, and which draws a current of I amps from a source V2 of volts ?
Group of answer choices

2VI

VI2

I2R

V28R​

Answer 1

Answer:

Correct option is

A

5Ω

Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance, one arrives at the usual mathematical equation that describes this relationship, I = V/R.

Rewriting this relation we arrive at R=

I

V

=

1.2A

6V

=5ohms.

Hence the resistance of the filament of the bulb is 5 ohms.