Grade IX Gravitation

A stone has a mass 40g and volume 30cm³ _{. Calculate the density of the stone.}

• 1g/cm3

• 1.3g/cm3

• 1.3kg/m3

A crown weighs 33N in air and 21N in water. What is the buyont force?

• 21N

• 12N

• 33N

A man displaces 750ml of water when jumped into a bath tub. What is the weight of displaced water when the density of water is 1000kg/m³

• 7500000N

• 7.5N

• 0.75N

A wooden box of dimension 25mX3mx1m is placed on soft sand. Which side of the box exert maximum pressure?

• 25X1

• 3X1

• 25X3

Pick the right option:

• When the ship floats on water , weight of the ship displaces equal weight of water

• When the ship floats on water , weight of the ship under the water displaces equal weight of water

• When the ship floats on water , weight of the ship under the water displaces lesser weight of water than the ship's weight

Suppose gravity of earth suddenly becomes zero, then in which direction will the moon begin to move if no other celestial body affects it?

Pick the right option?

• Moon will move in a straight line in the direction it was moving at that instant (tangential path)

• Moon will drop down towards the earth

• Moon will be attracted by the sun

Weight of the an object at the centre of the earth is _____

• infinite

• R times the weight at the surface of the earth

• zero

Weight of an person is about 1/6 times that of earth. He can lift a max mass of 15kg on earth. What will be the max mass, which can be lifted by the person on the moon with the same force applied?

• 15 kg as mass remains the same

• 90 kg (as mass x 6 )

• 1.5 kg ( as 1/6 weight on moon)