The graph shown below relates how the force acting on an object varies with time during a collision.
The area under the graph represents
the object's change of
F
t
The force acting on an object
varies as shown on the right. If
the mass of the object is 4 kg,
and it is initially at rest, find its
momentum at 8s.
force/N
t/s
2 4 6
0
20
8
When an object is falling freely under gravity its rate of change of momentum is equal to its:
Four objects A, B, C, and D, each of 1 kg are connected together by inextensible strings and pulled by a force of 10 N as shown.
10 N
A
B
C
D
Find the force exerted by B on C.
smooth
surface
A helicopter of mass 3,500 kg rises vertically with a constant velocity of
15 m/s. Find the net force acting on the helicopter
A machine gun fires bullets , each of mass m, onto a vertical wall at a rate of n bullets per second. If the speed of each bullet is v and they rebound from the wall at the same speed, find an expression for the average force exerted on the wall.
When a person is standing in a lift which is accelerating upwards, the magnitude of the force exerted on the man's feet by the floor is always:
Newton's third law discusses the forces of interaction between two objects. The following statements relate to the action and reaction forces in Newton's third law. Identify the incorrect statement.
Find the rate of change of momentum on a body if a force of 5 N were acting on it for a period of 3 s.
Two objects, P and Q of masses 3 kg and 7 kg respectively are accelerated along a horizontal surface by a force of 5 N as shown.
P Q
3kg 7kg
5 N
Find the magnitude of the force on P due to Q during this acceleration.