C9ii Gravitation

A stone is released from the top of a tower of height 19.6 m. Then its final velocity just before touching the ground will be:

• 384.16 m/ s

• 196 m/s

• 19.6 m/s

• 3841.4 m/s

The SI unit of G

• Ncm²/kg²

• Nm²kg²

• Nm²/kg²

• Nkg/m²

A ball is thrown up, the value of g will be?

• zero

• negative

• positive

• negligible

The upward force exerted by water on an object in it is called

• pressure

• thrust

• buoyancy

• drag

The relative density of an object is determined comparing its density with that of

• water

• air

• iron

• wood

According to Archimedes principle the upward force experiencing on a body immersed in it will be equal to

• the amount of water displaced

• the volume of water displaced

• the weight of the water displaced

• the area of the object in contact with the water

What is the difference between mass and weight ?( multiple select)

• Mass of an object is the quantity of matter contained in it whereas weight of an object is the force with which it is attracted towards the centre of earth

• Mass is a vector and weight is scalar

• Mass is constant whereas weight is not

• SI unit of mass is Kg and SI unit of weight is Newton

X =  $\frac{Density\ of\ subs\tan ce}{Density\ of\ water\ at\ 4\ ^0C}$  ,What is X here?

• Density

• Relative density

• Mass

• None

A coin and a feather are dropped together in a vacuum. Then

(a) the coin will reach the ground first

(b) the feather will reach the ground first

(c) both will reach the ground at the same time

(d) the feather will not fall down

• a

• b

• c

• d

an object has a mass 36 kg on earth find its weight on the moon (approximated values)

• 360 N

• 300 N

• 60 N

• 10 N