(a) 100 N (b) 90 N (c) 50 N (d) 10 N
Three bolcks are placed at rest on a smooth inclined
plane with force acting on m 1 parallel to the
inclined plane. The contact force between m 2 and
m 3 is
(a)
1 2 3
3
m m m F
m
(b) F m m g 1 2
(c)
3
1 2 3
m F
m m m (d) F m m m g^1 ^23
The accelerations of the two blocks are given then
the acceleration of block C is
(a) 1 /m s^2 upward (b) 1 /m s^2 down ward
(c) 2 /m s^2 up ward (c) 3 /m s^2 up ward
Two particles of mass m each are tied at the ends of
a light string of length 2a. The whole system is
kept on a frictionless horizontal surface with the
string held tight so that each mass is at a distance
‘a’ from the centre P (as shown in the figure). Now,
the mid-point of the string is pulled vertically
upwards with a small but constant force F. As a
result, the particles move towards each other on
the surface. The magnitude of acceleration, when
the separation between them becomes 2x, is
(a) 2 2 2
F a
m a x (b) 2 2 2
F x
m a x
(c)
2
F x
m a
(d)
2 2
2
F a x
m x
A particle is acted upon by a force of constant
magnitude which is always perpendicular to the
velocity of the particle, the motion of the particle
takes place in a plane. It follows that
(a) It moves in a straight line
(b) Its kinetic energy is constant
(c) Its velocity is constant
(d) Its acceleration is constant
A force F, making an angle with the horizontal,
acting on an object displaces it by 0.4m along the
horizontal direction. If the object gains kinetic
energy of 1J, the horizontal component of the force
is
(a) 2.5 N (b) 1.5 N (c) 4.5 N (d) 3.5 N
When a conservative force does positive work on
a body:
(a) The potential energy increases
(b) The potential energy decreases
(c) Total energy increases
(d) Total energy decreases
A block of mass m sliding down an incline at
constant speed is initially at a height h above the
ground, as shown in the figure. The coefficient of
kinetic friction between the mass and the incline is
. If the mass continues to slide down the incline
at a constant speed, how much energy is dissipated
by friction by the time the mass reaches the bottom
of the incline?
Work, Power & Energy
6.
7.
8.
9.
10.
(a) mgh/ (b) mghsin
(c) mgh/ sin (d) mgh
A ball is placed on a massless spring that is held at
an angle of with respect to the horizontal. The
