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प्रश्न
When is free fall possible?
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उत्तर
Free fall is only conceivable in the absence of air or vacuum. When a ball and a feather are thrown from a height, the ball falls to the ground first. In a vacuum, both the ball and the feather will end up on the ground.
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संबंधित प्रश्न
Which force is responsible for the moon revolving round the earth ?
When an object is dropped from a height, it accelerates and falls down. Name the force which accelerates the object.
Explain why, if a stone held in our hand is released, it falls towards the earth.
The values of g at six distances A, B, C, D, E and F from the surface of the earth are found to be 3.08 m/s2, 9.23 m/s2, 0.57 m/s2, 7.34 m/s2, 0.30 m/s2 and 1.49 m/s2, respectively.
(a) Arrange these values of g according to the increasing distances from the surface of the earth (keeping the value of g nearest to the surface of the earth first)
(b) If the value of distance F be 10000 km from the surface of the earth, state whether this distance is deep . inside the earth or high up in the sky. Give reason for your answer.
Name the force which pulled the apple off Isaac Newton’s tree.
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Solve the problem.
If the mass of a planet is eight times the mass of the Earth and its radius is twice the radius of the Earth, what will be the escape velocity for that planet?
What will be the weight of a person on earth, who weighs 9N on the moon?
A force acts for 10 s on a stationary body of mass 100 kg, after which the force ceases to act. The body moves through a distance of 100 m in the next 5 s. Calculate : The acceleration produced by the force
Figure shows the velocity-time graph of a particle of mass 100 g moving in a straight line. Calculate the force acting on the particle.
(Hint : Acceleration = Slope of the v-t graph)
A force causes an acceleration of 10 m s-2 in a body of mass 500 g. What acceleration will be caused by the same force in a body of mass 5 kg?
A car is moving with a uniform velocity 30 ms-1. It is stopped in 2 s by applying a force of 1500 N through its brakes. Calculate the following values : The retardation produced in car.
How is the acccelaration due to gravity on the surface of the earth realted to its mass and radius ?
The value of gravitational acceleration at the centre of earth is zero.
Write scientific reason.
The value of gravitational acceleration (g) decreases as we go deep inside the earth.
Write scientific reason.
When we drop a feather and a stone at the same time from a height the stone reach the earth faster than a feather.
The mass and weight of an object on earth are 5 kg and 49 N respectively. What will be their values on the moon? Assume that the acceleration due to gravity on the moon is 1/6th of that on the earth.
Calculate the escape velocity on the surface of the moon given the mass and radius of the moon to be 7.34 × 1022 kg and 1.74 × 106 m respectively.
(Given: G = 6.67 × 10-11 Nm2/kg2)
