For the first one 320
second
1200W
Data
R = 12 Ω ∆V = 120V I =? P =?
Solution:
According to Ohm’s law,
∆V = I R
I = ∆V / R
= 120 / 12
= 10 A
Power P = I ∆V
= 10 x 120
= 1200 W
Third
∆V = 120 V P = 60 W I =? R =?
Use the formula, P = I ∆V
I = P / ∆V = 60 / 120 = 0.5 A
∆V = I R
R = ∆V / I = 120 / 0.5 = 240 Ω
