Advertisements
Advertisements
Question
Sumit does 600 J of work in 10 min and Amit does 300 J of work in 20 min. Calculate the ratio of the powers delivered by them.
Advertisements
Solution
Sumit: Work done, w1 = 600 J
Time taken, t1 = 10 min = 600 sec
Power, p1 = `w_1/t_1`
= `600/600`
= 1 W
Amit: Work done, w2 = 300 J
Time taken, t2 = 20 min = 1200 sec
Power, p2 = `w_2/t_2`
= `300/1200`
= `1/4`
= 0.25 W
∴ Ratio of Powers = `p_1/p_2`
= `1/(1/4)`
= 4 : 1
APPEARS IN
RELATED QUESTIONS
The unit in which we pay the cost of electricity is ..........
In a household electrical circuit, the appliance are connected in ............with the mains.
State the purpose of kWh meter.
Name the unit in which you pay the cost of your electricity bill. How is it related to joule?
Draw a labelled diagram with the necessary switches to connect a bulb, a fan and a plug socket in a room with the mains. In what arrangement will you connect them to the mains?
An electric iron of power 1.5 kW is used for 30 minutes to press the clothes. Calculate the electrical energy consumed in
- kilowatt-hour
- joule.
State and define the household unit of electricity.
What is the resistance, under normal working conditions, of an electric lamp rated at '240 v, 60 W' ? If two such lamps are connected in series across a 240 V mains supply, explain why each one appears less bright.
An electrical appliance is rated as 60 W – 150 V.
How much current will flow through the appliance when in use?
Our body can pass electricity through it.
