Gravitation

An object is thrown vertically upwards with a velocity u, the greatest height h to which it will rise before

falling back is given by

• u / g

• u^2 / 2g

• u^2 / g

• u / 2g

The value of on the surface of the moon

• is the same as on the earth

• is less than that on the earth

• is more than that on the earth

• keeps changing day by day

The mass of moon is about 0.012 times that of earth and its diameter is about 0.25 times that of earth.

The value of G on the moon will be

• less than that on the earth

• more than that on the earth

• same as that on the earth

• about one-sixth of that on the earth

The atmosphere consisting of a large number of gases is held to the earth by

• Wind

• Clouds

• Earth’s magnetic field

• Gravity

The force of araction between two unit point masses separated by a unit distance is called :

• Gravitational potential

• Acceleration due to gravity

• Gravitational field strength

• Universal gravitational constant

The weight of an object at the centre of the earth of radius R is :

• Zero

• R times the weight at the surface of the earth

• Infinite

• 1 / R^2 times the weight at the surface of the earth

Two objects of different masses falling freely near the surface of moon would :

• have same velocities at any instant

• have different accelerations

• experience forces of same magnitude

• undergo a change in their inertia

The value of acceleration due to gravity of earth:

• is the same on equator and poles

• is the least on poles

• is the least on equator

• increases from pole to equator

The law of gravitation gives the gravitational force between:

• the earth and a point mass only

• the earth and the sun only

• any two bodies having some mass

• any two charged bodies only

The value of quantity G in the formula for gravitational force :

• depends on mass of the earth only

• depends on the radius of earth only

• depends on both mass and radius of earth

• depends neither on mass nor on radius of earth