Book: NCERT - Science
Chapter: 12. Electricity
Subject: Physics - Class 10th
Q. No. 16 of Exercise-Pg-221
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Which uses more energy, a 250 W TV set in 1hr or a 1200 W toaster in 10 minutes ?
(i) For TV set:
Power, P= 250W=
Time, t = 1 h
So, Electric energy, E= P x t = 0.25Kw x 1 h = 0.25 kWh
(ii) For toaster:
Power, P= 250W= 
Time, t= 10 min= 
So, Electric energy, E= P x t= 1.2 kW x 
= 0.20kWh
From the above calculations, it is clear that the TV set uses more energy (0.25 kWh) whereas toaster uses less energy (0.20 kWh).
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