A 60 W bulb burns for 2 hours. The total energy consumed in kWh is:
A0.06
B0.12
C0.36
D1.20
Answer & Solution
Correct answer: B. 0.12
1. Energy = power × time.
2. Power = 60 W = 0.060 kW.
3. Time = 2 h.
4. Energy = 0.060 × 2 = 0.120 kWh.
_Source: NCERT Class 11 Physics Ch 5, §5.10 Power, p. 85_
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