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Laws of motion

Two billiard balls each of mass 0.05 kg moving in opposite directions with speed 6 m s
-1
collide and rebound with the same speed. What is the impulse imparted to each ball due
to the other ?

28/10/2024

Physics

11th (Science)

Laws of motion

A nucleus is at rest in the laboratory frame of reference. Show that if it disintegrates
into two smaller nuclei the products must move in opposite directions.

28/10/2024

Physics

11th (Science)

Laws of motion

Two masses 8 kg and 12 kg are connected at the two ends of a light inextensible
string that goes over a frictionless pulley. Find the acceleration of the masses, and
the tension in the string when the masses are released.

28/10/2024

Physics

11th (Science)

Laws of motion

Two bodies of masses 10 kg and 20 kg respectively kept on a smooth, horizontal
surface are tied to the ends of a light string. A horizontal force F = 600 N is
applied to (i) A, (ii) B along the direction of string. What is the tension in the
string in each case?

28/10/2024

Physics

11th (Science)

Laws of motion

Figure 4.16 shows the position-time graph of a particle of mass 4 kg. What is
the (a) force on the particle for t < 0, t > 4 s, 0 < t < 4 s? (b) impulse at t = 0 and t = 4 s ? (Consider one-dimensional motion only).

28/10/2024

Physics

11th (Science)

Laws of motion

A man of mass 70 kg stands on a weighing scale in a lift which is moving
(a) upwards with a uniform speed of 10 m s-1
,
(b) downwards with a uniform acceleration of 5 m s-2
,
(c) upwards with a uniform acceleration of 5 m s-2
.
What would be the readings on the scale in each case?
(d) What would be the reading if the lift mechanism failed and it hurtled
down freely under gravity ?

28/10/2024

Physics

11th (Science)

Laws of motion

A bob of mass 0.1 kg hung from the ceiling of a room by a string 2 m long is
set into oscillation. The speed of the bob at its mean position is 1 m s-1
.
What is the trajectory of the bob if the string is cut when the bob is (a) at one
of its extreme positions, (b) at its mean position.

28/10/2024

Physics

11th (Science)

Laws of motion

A truck starts from rest and accelerates uniformly at 2.0 m s-2. At t = 10 s, a
stone is dropped by a person standing on the top of the truck (6 m high from
the ground). What are the (a) velocity, and (b) acceleration of the stone at t =
11s ? (Neglect air resistance.)

28/10/2024

Physics

11th (Science)

Laws of motion

A body of mass 0.40 kg moving initially with a constant speed of 10 m s-1 to
the north is subject to a constant force of 8.0 N directed towards the south
for 30 s. Take the instant the force is applied to be t = 0, the position of the
body at that time to be x = 0, and predict its position at t = –5 s, 25 s, 100 s.

28/10/2024

Physics

11th (Science)

Laws of motion

A rocket with a lift-off mass 20,000 kg is blasted upwards with an initial
acceleration of 5.0 m s-2. Calculate the initial thrust (force) of the blast.

28/10/2024

Physics

11th (Science)