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प्रश्न
Explain the transformation of energy in the following cases :
(i) A ball thrown upwards.
(ii) A stone dropped from the roof of a building.
उत्तर
(i) When a ball is thrown upwards, its kinetic energy at the thrower's hand is transformed into potential energy at the maximum height. As the stone continues to move upwards, its potential energy gradually increases, but its kinetic energy decreases as velocity of the stone decreases.
(ii) When a stone is dropped from a height its potential energy at the height is transformed into kinetic energy on reaching the ground. As the stone descends, its potential energy gradually decreases and its kinetic energy increases.
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संबंधित प्रश्न
A stone of mass 500 g is thrown vertically upwards with a velocity of 15 m/s. Calculate:
- the potential energy at the greatest height,
- the kinetic energy on reaching the ground, and
- the total energy at its half-way point.
Is energy a vector quantity?
State whether the object possess kinetic energy, potential energy, or both :
A stretched spring lying on the ground ____________.
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Describe the energy changes which take place in a radio.
Write the energy transformations which take place in an electric bulb (or electric lamp).
What do you understand by the term 'transformation of energy"? Explain with an example.
Name the energy transfers which occur when :
an electric ball rings
Name the energy transfers which occur when : there is a picture on a television screen
