What is Transformation of Energy
It is change of energy from one form to another
Examples of Transformation of Energy
Dropping of brick from Height
In this case, potential energy gets transformed into kinetic enrrgy
Potential Energy → Kinetic Energy
Explanation
Suppose brick is lying at the roof of House
It currently has potential energy
When it is dropped from roof to earth
Its potential energy gets converted into kinetic energy
As it falls down on earth, its speed increases (this is because its potential energy keeps on decreasing and kinetic energy keeps
on increasing)
Thus there is transformation of Potential energy into kinetic energy when
Brick Thrown upwards
In this case, kinetic energy is transformed into potential energy
Kinetic Energy → Potential Energy
Explanation
When a brick is thrown upwards,its speed keeps on decreasing
This is because kinetic energy in brick keeps in decreasing and potential energy keeps on increasing
Thus there is transformation of Kinetic energy into potential energy when a brick is thrown upwards.
Hydroelectric Power House
In this case, potential energy of water is transformed into kinetic energy which later gets transformed into Electrical Energy
Potential Energy → Kinetic Energy → Electric Energy
Explanation
in a hydroelectric power house,electricity is generated with the help of water
Water is made to fall on turbines at a great speed which make turbines move (generating kinetic energy)
This kinetic energy is convered into electrical energy with the help of generator
Energy Changes When a Body Does Work
When we do some work, we feel tired
This is because we lose energy
This energy which we lose is gained by some other body
Example 1
When we push a heavy Box, we feel tired and lose energy
This energy which we lose is gained by box in the form of kinetic energy
This kinetic energy makes the box move
Example 2
When we rub our hands,it produces heat
When we rub our hands, the kinetic energy is produced while rubbing the hands.
This kinetic energy is produced by lose of some energy from our body.
Later, the kinetic energy of our hands converted into heat energy.
Example 3
When we lift a heavy box
When we lift a box, we feel tired and lose energy.
This energy which we lose is gained by the box in the form of potential energy.
Questions
NCERT Question 21 - A freely falling object eventually stops on reaching the ground. What happened to its kinetic energy?
