Question

8. An electrical appliance has rating 100W, 120V. The resistance of element of
appliance when in use is :
a)1.2Ω b)144Ω c)120Ω d)100Ω

Answer 1

Explanation:

a is the answer that is 1.2

Answer 2

Answer:

Option (B) : 144Ω

Explanation:

Given:

Power (P) = 100W

Potential difference (V) = 120v

To find:

Resistance (R)

Solution:

We know that

Power = Potential difference × Current

=> P = V × I

=> I = P/V

=> I = 100/120

=> I = 5/6 A

Now

Resistance = Potential difference/ Current

=> R = V/I

=> R = 120/(5/6)

=> R = (120 × 6)/5

=> R = 24 × 6

=> R = 144Ω