Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
Solution:
The energy consumed by electrical appliances is given by the equation
H = Pt, where P is the power of the appliance and t is the time
Using this formula, the energy consumed by a TV of power ration 250 W, can be calculated as follows:
H = 250 W × 3600 seconds = 9 × 105 J
Similarly, the energy consumed by a toaster of power rating 1200 W is
H = 1200 W × 600 s = 7.2 × 105 J
From the calculations, it can be said that the energy consumed by the TV is greater than the toaster.
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