Advertisements
Advertisements
Question
Solution
We know that, E =Pt
Given, P = 60 W= 0.06 kW
and, t = 50 hours
.·. E=0.06 x 50=3kWh
APPEARS IN
RELATED QUESTIONS
If a bulb of 60W is connected across a source of 220V, find the current drawn by it.
Define kilowatt-hour.
Which of the following is likely to be the correct wattage for an electric iron used in our homes?
(a) 60 W
(b) 250 W
(c) 850 W
(d) 2000 W
Two lamps, one rated 220 V, 50 W and the other rated 220 V, 100 W, are connected in serieswith mains of 220 V. Explain why does the 50 W lamp consume more power
An electrical appliance having a resistance of 200Ω is operated at 200 V. Calculate the energy consumed by the appliance in 5 minutes (i) in joules (ii) in kWh.
What is the resistance, under normal working conditions of a 240 V electric lamp rated at 60 W? If two such lamps are connected in series across a 240 V mains supply, explain why each one appears less bright.
State two advantages of filling an inert gas in an evacuated electric filament lamp.
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the energy supply in kWh to the three heaters in 5 hour.
Out of the three fuses with current ratings 5A, 10A, 15A, which one is to be connected in a geyser circuit marked 3 kW, 220V? Give reason for your answer.
Compare the power used in the 2 Ω resistor in each of the following circuits:
- a 6 V battery in series with 1 Ω and 2 Ω resistors
- a 4 V battery in parallel with 12 Ω and 2 Ω resistors.