Gravitation Tes...

If the Earth is replaced by a small point sized particle of the same mass, its geodesic centre being the same, how will the force of gravity change at the present surface of Earth? (Assuming Earth to be a perfect sphere)

At what height above the Earth's surface does the acceleration due to gravity fall to 1% of its value at the Earth's surface?

Two planets have radii r₁ and r₂ and densities d₁ and d₂, respectively. The ratio of the values of acceleration due to gravity on them will be

Which of the following statements are true?

(i) Orbital velocity is more than escape velocity.
(ii) Escape velocity is times the orbital velocity.
(iii) Orbital velocity increases with radius.
(iv) A body with a velocity equal to the orbital velocity will orbit the planet in a circular path.

A satellite going around the Earth in a circular orbit loses some energy due to a collision. If its speed is v and distance from the Earth is d, which of the following is correct?

A satellite having circular orbit about the Earth has a kinetic energy E_x. What is the minimum amount of energy to be added so that it escapes from the Earth?

Two planets 'A' and 'B' of same mass and same radius are shown in the figure. ρ₁ and ρ₂ are the densities of the materials in the planets and ρ₁ > ρ₂. If the values of acceleration due to gravity on the surface of the planets A and B are g_A and g_B respectively, then

The gravitational force between two bodies is 'F'. If the mass of each body is doubled and distance between them is halved, then the force between them will be

A satellite is revolving around the planet in an orbit of radius 'r' with orbital velocity 'v'. It is shifted to the new orbital radius 2r, the new orbital velocity is

Two bodies - P and Q - of masses 1 kg and 16 kg, respectively, are placed at a distance of 10 m from each other. Where should a body of mass 1 kg be placed between them so that the gravitational forces due to P and Q on it are equal and opposite?

Consider a heavenly body whose mass is thrice that of Earth and radius is twice that of Earth. What is the weight of a block on this heavenly body if the weight of the block on Earth is 400 N?

Earth is assumed to be a sphere of radius R. A platform is arranged at a height R from the surface of Earth. The escape velocity of a body from this platform is fv_e, where v_e is its escape velocity from the surface of Earth. The value of f is

Which of the following graphs represents the motion of a planet moving around the sun?

The pressure of water at the bottom in a lake is times the pressure at half the depth, where the water barometer reads 10 m. The depth of the lake is

An iron ball is weighed in air and then in water by a spring balance. Where does it weigh more?

A boy carries a fish in one hand and a bucket of water in the other hand. If he places the fish in the bucket, the weight now carried by him

A fisherman hooks an old log of wood of weight 12 N and volume 1000 cm³. He pulls the log half way out of water. The tension in the string at this instant is

A solid cylinder floats on water with 4/5 of its volume inside water. The density of the material of the cylinder is

Two solids A and B float on a liquid. It is observed that A floats with (1/2) of its volume immersed and B floats with (2/3) of its volume immersed. Compare the densities of A and B.

The spring balance A reads 2 kg with a block m suspended from it. A balance B reads 5 kg when a beaker with liquid is put on the pan of the balance. The two balances are now so arranged that the hanging mass is inside the liquid in the beaker, as shown in the figure. In this situation,