Answer:
Resistance of the lamp (r) = 156.52 ohm (Approx.)
Explanation:
Given:
Total power p = 140 W
Resistance of the coffee maker = 300 Ohm
Voltage v = 120 V
Find:
Resistance of the lamp (r)
Computation:
We know that
p = v² / R
SO,
Total power p = [Voltage²/Resistance of the lamp (r)] + [Voltage²/Resistance of the coffee maker]
140 = [120² / r] + [120²/300]
140 = 120²[1/r + 1/300]
140 = 14,400 [1/r + 1/300]
Resistance of the lamp (r) = 156.52 ohm (Approx.)
