Force and laws of motion Worksheet-7
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State the relation between the momentum of a body and the force acting on it.
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What is the unit of force ?
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Define one newton force.
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What is the relationship between force and acceleration ?
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If the mass of a body and the force acting on it are both doubled, what happens to the acceleration ?
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Name the physical quantity whose unit is 'newton'.
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Which physical principle is involved in the working of a jet aeroplane ?
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Name the principle on which a rocket works.
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Is the following statement true or false :
A rocket can propel itself in a vacuum.
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What is the force which produces an acceleration of 1 m/s2 in a body of mass 1 kg ?
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Find the acceleration produced by a force of 5 N acting on a mass of 10 kg.
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A girl weighing 25 kg stands on the floor. She exerts a downward force of 250 N on the floor. What force does the floor exert on her?
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Name the physical quantity which makes it easier to accelerate a small car than a large car.
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Explain the meaning of the following equation :
F = m × a
Where symbols have their usual meanings.
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To take the boat away from the bank of a river, the boatman pushes the bank with an oar. Why?
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Why does a gunman get a jerk on firing a bullet?
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If action is always equal to reaction, explain why a cart pulled by a horse can be moved.
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Explain how a rocket works.
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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 ?
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If a man jumps out from a boat, the boat moves backwards. Why ?
Answer:
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where F is force and m is momentum.
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newton
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A Newton is that force which when acting on a body of mass 1 kg produces an acceleration of 1 m/s2 in it.
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Force = mass × acceleration.
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Acceleration remains the same
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force
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Principle of conservation of momentum
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True
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1 newton (1 N)
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0.5 m/s2
Using Force = mass × acceleration.
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250 N
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Mass (of the car)
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