wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

(a) Write two points of difference between electric energy and electric power.
(b) Out of 60 W and 40 W lamps, which one has a higher electrical resistance when in use.
(c) What is commercial unit of electric energy?
Convert it into Joules.

Open in App
Solution

Sr. No.Electric EnergyElectric power(i)Electrical energy consumed by anIt is the rate of whichelectrical appliance is given byelectrical energy isthe product of its power ratingconsumed.and time for which it is used.(ii)It is measured in kilowatt hour (kWh).It is measured in watt (W) orkilowatt (kW).

(b) We know, power (P) =V2R
i.e. At same voltage, power (P) is inversely proportional to resistance (R).
40 W lamp has higher resistance.

(c) The commercial unit of electrical energy is kWh.
1 kWh=1000 W×1 h =1000 W×3600 s
=36×105 Ws
=3.6×106 J.

flag
Suggest Corrections
thumbs-up
3
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Household Electrification
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon