ARMY PUBLIC SCHOOL, GOLCONDA
Class 9 – Physics
F.A.3 REVISION
(WORKSHEET)
1.
An
object is put in four liquids having different densities as, d1,d2
,d3 ,d4 . If d1
> d2 > d3 > d4. Which liquid exerts
the maximum upward force? Why?
2.
When
a golf ball is lowered in a measuring cylinder containing water, the water
level rises up by 30 cm3 when the ball is completely submerged. If
the mass of the ball in air is 33 g.
a)
Find
density of object.
b) State whether ball will sink or float.
c)
Mass
of water displaced.
d) Buoyant force acting on ball.
3.
5 N
of force acts on material A over the area of 20 m2 whereas 20 N of
force acts on area 40 m2 of material B. Which has exerted the
greater pressure? Calculate the ratio of pressure exerted by the two.
4.
A
boy throws a rubber ball vertically upwards. What type of work, positive or
negative, is done :
a)
By the
force applied by the boy?
b) By the gravitational force of earth?
5.
In which
of the following cases the work has done by a force will be maximum: when the
angle between the direction of force and direction of motion is 00 ,
900 , 1800 ?
6.
The relative
density of four liquids P, Q, R, and S are 1.26, 1.0, 0.84, and 13.6 respectively.
Which of the following liquid will exert maximum and minimum upthrust on
object, if object immersed in these liquids?
7.
Which
would have a greater effect on the kinetic energy of an object: doubling the mass
or doubling the velocity?
8.
Two bodies
of equal mass move with uniform velocity v
and 3v respectively. Find the ratio
of their kinetic energy.
9.
A mass
of 2 m3 of steel is 15600 Kg. when this mass completely immersed in
water, calculate:
a)
Density
of object in Kg/m3.
b) State whether the steel mass will sink
or float?
c)
Mass
of water displaced.
d) Buoyant force acting on steel.
10.
A force
of 300 N acts on a metallic cuboid of dimensions 30 cm X 20 cm X 15 cm. With which face the cuboid
should rest, so that the pressure exerted by the cuboid on the floor is minimum?
