Question

Which uses more energy, a 250w TV set for 1 hour or a 1200w toaster for 10 minutes

Answer 1

250×60=12500 (in minutes.)

1200×10=12000

so TV set uses more energy by 50w

Answer 2

⇒ Power (P) TV = 250 W

⇒ Time Taken (t) = 1 hr

⇒ Heat = Power × Time

⇒ H = Pt

⇒ 250 W × 1hr

⇒ 250 Wh

therefore , the energy consumed by 250 W TV set in 1 hr = 250 Wh.

⇒ Power (P) Toaster = 1200 W

⇒ Time Taken (t) = 10 minutes

⇒ H = Pt

⇒ 1200 × 10/60

⇒ 200 Wh.

Therefore, Energy consumed by TV set is more than by the toaster in the giving timing.