Gravitation — Previous-Year Questions

Q1. Force of gravity between Earth (5.97 × 10²⁴ kg) and Moon (7.35 × 10²² kg) at distance 3.84 × 10⁸ m:

Q2. If the distance between two bodies is halved, gravitational force becomes:

Q3. Cavendish's experiment measured:

Q4. Inside a uniform spherical shell, gravity is:

Q5. Newton's law of gravitation is:

Q1. At a height equal to Earth's radius, g_h is:

Q2. At what depth is g = g₀/2?

Q3. At the center of Earth, g equals:

Q4. An object at height h ≪ R has approximate g reduction of:

Q5. Apparent g at the equator is LESS than at the poles because:

Q1. Gravitational potential at Earth's surface (M = 6×10²⁴ kg, R = 6.4×10⁶ m):

Q2. Potential energy of mass m at potential V is:

Q3. Gravitational field is related to potential by:

Q4. Two equal point masses M at distance 2r. Potential at midpoint:

Q5. Surfaces of constant gravitational potential are:

Q1. Escape velocity from Earth's surface (g = 9.8, R = 6.4×10⁶):

Q2. If a planet has the same density as Earth but twice the radius, its escape velocity:

Q3. Escape velocity from height R above surface (h = R):

Q4. Ratio v_esc / v_orb at any given r is:

Q5. If the mass of a body is doubled but its radius unchanged, escape velocity:

Q1. Orbital velocity of a satellite at r = 2R from Earth's center:

Q2. If orbital radius doubles, orbital velocity:

Q3. Time period of a satellite at r = 4R (Earth) is:

Q4. Orbital velocity of a body just above Earth's surface (g = 9.8, R = 6.4×10⁶ m):

Q5. Energy required to lift a satellite from low Earth orbit to a higher orbit at 2R is:

Q1. Kepler's third law states:

Q2. Mars has semi-major axis 1.524 AU. Its orbital period:

Q3. Kepler's second law is equivalent to:

Q4. A planet moves SLOWER when:

Q5. Kepler's laws apply to:

Q1. If the radius of Earth is halved keeping mass same, escape velocity becomes:

Q2. The ratio of orbital velocity to escape velocity for a satellite near Earth's surface is:

Q3. A satellite orbits Earth at height R above the surface (R = radius of Earth). Its orbital speed is:

Q4. Two planets have radii r₁ and r₂, densities ρ₁ and ρ₂. Ratio of escape velocities:

Q5. Energy required to move a satellite from orbit of radius 2R to 3R is: