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प्रश्न
The total energy of an object falling freely towards the ground ______.
पर्याय
decreases
remains unchanged
increases
increases in the beginning and then decreases
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उत्तर
The total energy of an object falling freely towards the ground remains unchanged.
Explanation:
In an object falling freely to the ground, as the object's distance from the ground decreases, so does the potential energy stored in the object; But the kinetic energy of a freely falling object increases as the velocity increases over time. Thus, the potential energy lost by an object in free fall is equal to the kinetic energy it gains, i.e. the total energy of the object remains constant.
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संबंधित प्रश्न
What do you mean by acceleration due to gravity?
A stone is thrown vertically upward with an initial velocity of 40 m/s. Taking g = 10 m/s2, find the maximum height reached by the stone. What is the net displacement and the total distance covered by the stone?
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Explain why, if a stone held in our hand is released, it falls towards the earth.
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(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.
What will be the weight of a person on earth, who weighs 9N on the moon?
i) If g = GM/r2 then where will the value of g be high at Goa Beach or on top of Mount Everest?
For freely falling object we can write the Newton’s second equation of motion as …..
A metal ball of mass 5 kg falls from a height of 490 m. How much time it will take to reach the ground? (g = 9.8 m/s2)
A force of 10 N acts on a body of mass 5 kg. Find the acceleration produced.
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
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.
Explain why:
Objects fall to the earth.
The value of gravitational acceleration (g) is ______.
The free fall of an object is possible only in ______.
Read the given passage carefully and answer the questions.
| We know that the force of gravity due to the earth acts on each and every object. When we were holding the stone in our hand, the stone was experiencing this force, but it was balanced by a force that we were applying on it in the opposite direction. As a result, the stone remained at rest. Once we release the stone from our hands, the only force that acts on it is the gravitational force of the earth and the stone falls down under its influence. Whenever an object moves under the influence of the force of gravity alone, it is said to be falling freely. Thus the released stone is in a free fall. In free fall, the initial velocity of the object is zero and goes on increasing due to the acceleration due to the gravity of the earth. During free fall, the frictional force due to air opposes the motion of the object and a buoyant force also acts on the object. Thus, true free fall is possible only in a vacuum. |
- Complete the following statement by choosing the right option.
The stone held in the hand is stable because on it ......- two unbalanced forces are exerted.
- only the gravitational force of the earth is exerted.
- gravitational force of the earth is not exerted.
- two balanced forces are exerted.
- Why does free fall not happen on the earth?
- Why does the velocity of the object increase during the free fall?
- Which type of force exerts on the object during free fall?
- Why does free fall happen only in a vacuum?
