16
Question Question 16
Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?
Given,
Power of TV set = P1 = 250 W
Time taken by TV set = t1 = 1 hr = 3600 s
Power of toaster = P2 = 1200
Time taken by toaster = t2 = 10 minutes = 600 s
We know, energy consumed (H) = Pt
Energy consumed by TV set:
E1 = 250 × 3600 = 900000 J = 9 × 105 J
Energy consumed by toaster:
E2 = 1200 × 600 = 720000 = 7.2 × 105 J
As E1 > E2, hence, energy consumed by the TV set is greater than the toaster.