English

Define Kilowatt-hour.

Advertisements
Advertisements

Question

Define kilowatt-hour. 

One Line Answer
Advertisements

Solution 1

One kilowatt-hour is the amount of electrical energy consumed when an electrical appliance having a power rating of one kilowatt is used for one hour.

shaalaa.com

Solution 2

Kilowatt hour is the unit of work.

Since, power × time = work

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Electricity - Exercise 7

APPEARS IN

Lakhmir Singh Physics [English] Class 10
Chapter 4 Electricity
Exercise 7 | Q 29.3

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

At what frequency is AC supplied to residential houses?


Name two safety devices which are connected to the live wire of a household electric circuit


A 2 kWh heater, a 200 W TV and three 100 W lamps are all switched on from 6 p.m. to 10 p.m. What is the total cost at Rs 5.50 per kWh?


When an electric lamp is connected to 12 V battery, it draws a current of 0.5 A. The power of the lamp is:   

(a) 0.5 W
(b) 6 W
(c) 12 W
(d) 24 W


The unit for expressing electric power is: 

(a) volt
(b) joule
(c) coulomb
(d) watt


Explain why, filament type electric bulbs are not power efficient.


Electrical power p is given by the expression P = (Q × V) ÷ time. Express the power P in terms of current and resistance explaining the meaning of symbols used there in.


A current of 0.2 A flows through a wire whose ends are at a potential difference of 15 V.
calculate:
(i) the resistance of the wire and
(ii) the heat energy produced in 1 minute.


Two resistors A and B of resistance 4 Ω and 6 Ω respectively are connected in parallel. The combination is connected across a 6 volt battery of negligible resistance. Calculate: (i) the power supplied by the battery, (ii) the power dissipated in each resistor.


A geyser is rated 1500 W, 250 V. This geyer is connected to 250 V mains. Calculate:
(i) the current drawn
(ii) the energy consumed in 50 hours, and
(iii) the cost of energy consumed at Rs. 4.20 per kWh


A simple electric circuit has 24 V battery and a resistor of 60 Ω. What will be the current in the circuit? The resistance of the connecting wires is negligible.


Name the commercial unit of electrical energy.

A radio set of 60 W runs for 50 hours. How much electrical energy is consumed? Give your answer in kWh.

An electric bulb of resistance 500 Ω draws current 0.4 A from the source. Calculate:

  1. the power of bulb and
  2. the potential difference at its end.

Two lamps are rated 220V, 50W and the other rated 220V, 100W are connected in series with the mains of 220 V. Explain, why the 50W lamp glows more?


An Electric bulb is marked 100 W, 230 V. What how long would this lamp take to consume one unit of electricity?


1 kWh = ____________


In the given figure, the emf of the cell is 2.2 V, and if internal resistance is 0.6 Ω. Calculate the power dissipated in the whole circuit.


1 kWh = ______ J.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×