Answer:
True
Step-by-step explanation:
Let u and v are initial and final speeds of an object. The momentum of an object is then given by :

Where
m is mass of the object
Also, the impulse-momentum theorem says that, impulse is equal to the change in momentum i.e.

It means, the magnitude of the change in momentum is directly proportional to the length of time (delta t) during which the force acts on the object. Hence, the given statement is true.