Physics 9 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 * u / 2g
• u * u / g
• u / g
• u / 2g

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 :

• same as that on the earth
• less than that on the earth
• more than that on the earth
• about one-sixth of that on the earth

The value of g on the surface of the moon:

• is less than that on the earth
• keeps changing day by day
• is the same as on the earth
• is more than that on the earth

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

• gravity
• earth's magnetic field
• winds
• clouds

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

• universal gravitational constant
• gravitational potential
• acceleration due to gravity
• gravitational field strength

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 * R) 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 least on equator
• is the same on equator and poles
• is the least on poles
• increases from pole to equator

The law of gravitation gives the gravitational force between :

• any two bodies having some mass
• the earth and a point mass only
• the earth and the sun only
• any two charged bodies only

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

• depends neither on mass nor on radius of earth
• depends on mass of the earth only
• depends on the radius of earth only
• depends on both mass and radius of earth