Advertisements
Advertisements
प्रश्न
Derive the relation between commercial unit of energy (kWh) and SI unit of energy (joule).
उत्तर
We can establish a relation between kilowatt-hour (kWh) and Joule (J) as –
1 kilowatt-hour = 1 kilowatt for 1 hour
= 1000 watt for 1 hour
But,
`1 "watt" = (1 "Joule")/(1 "s")`
So ,
1 kilowatt - hour = 1000 `"Joules"/"second"` for 1 hour
= `1000 "Joules"/"seconds" 60 xx 60 "seconds"`
= `3.6 xx 10^6` J
APPEARS IN
संबंधित प्रश्न
Write true or false of the following statement.
In an electric fan, electrical energy changes into the mechanical energy.
Write true or false of the following statement.
One form of energy cannot be converted into another form.
Fill in the blank
Cooking gas converts _______ energy into heat energy.
Fill in the blank
The S.I.unit of energy is ______
What is potential energy ? State its unit.
Name two units of power bigger than watt.
- Take two aluminium channels of different lengths.
- Place the lower ends of the channels on the floor and hold their upper ends at the same height.
- Now take two balls of the same size and weight and release them from the top end of the channels. They will roll down and cover the same distance.
- At the moment of releasing the balls, which energy do the balls have?
- As the balls roll down which energy is converted into which other form of energy?
- Why do the balls cover the same distance on rolling down?
Note: The question is wrong. It should be "Why do the balls cover the same distance after rolling down"? - What is the form of the eventual total energy of the balls?
- Which law related to energy does the above activity demonstrate? Explain.
If the energy of a ball falling from a height of 10 metres is reduced by 40%, how high will it rebound?
The capacity that an object has for doing work is called ______.
Define energy?
