Question
Figure below shows the position-time graph of a particle of mass 4 kg.
What is the:
(a) force on particle for,
t<0; t>4s; 0<t<4s?
(b) impulse at t = 0 and t = 4s?
Solution
(a) From the given graph, for t < 0, and t > 4s, the position of particle does not change.
Therefore, the particle is at rest and for 0 < t < 4s the position-time graph is a straight line.
This implies the velocity of particle is constant.
Therefore,
Acceleration of particle for t < 0, t < 4s and 0 < t < 4s is zero. Hence, no force acts on the particle.
b) We know, the slope of the position-time graph is velocity. Therefore, velocity of particle in interval 0 < t < 4 is,
Therefore, the particle is at rest and for 0 < t < 4s the position-time graph is a straight line.
This implies the velocity of particle is constant.
Therefore,
Acceleration of particle for t < 0, t < 4s and 0 < t < 4s is zero. Hence, no force acts on the particle.
b) We know, the slope of the position-time graph is velocity. Therefore, velocity of particle in interval 0 < t < 4 is,
