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प्रश्न
State Newton’s third law of motion and give two examples to illustrate the law.
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उत्तर
According to Newton’s third law of motion, whenever one body exerts a force on another body, the second body exerts an equal and opposite force on the first body.
Examples:
(i) Jet airplanes utilize the principle of action and reaction. In the modern jet aircraft, the hot gases obtained by the rapid burning of fuel rush out of a jet from the rear end of the aircraft at a great speed. The equal and opposite reaction of the backward-heading gases pushes the aircraft forward at a great speed.
(ii) While rowing a boat, the boatman pushes the water backwards with the oars. The water exerts an equal and opposite push on the boat which makes the boat move forward. In fact, harder the boatman pushes back the water with the oars, greater is the reaction force exerted by water and faster moves the boat, in forward direction.
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संबंधित प्रश्न
A stone of 1 kg is thrown with a velocity of 20 m s−1 across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice?
According to the third law of motion, when we push on an object, the object pushes back on us with an equal and opposite force. If the object is a massive truck parked along the roadside, it will probably not move. A student justifies this by answering that the two opposite and equal forces cancel each other. Comment on this logic and explain why the truck does not move.
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A rocket can propel itself in a vacuum.
Explain how a rocket works.
Do action and reaction act on the same body or different bodies ? How are they related in magnitude and direction ? Are they simultaneous or not ?
If a man jumps out from a boat, the boat moves backwards. Why ?
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when person A standing on roller skates pushes another person B (also standing on roller skates) and makes him move to the right side, then the person A himself gets moved to the left side by an equal distance.
According to the third law of motion, action and reaction :
While catching a cricket ball the fielder lowers his hands backwards. Why?
Why do the action and reaction forces in a pair not cancel each other out?
