Question

A constant force act on an object of mass 5 kg for a duration of 2 seconds it
increases the object velocity from 3 metre per second to 7 metre per second find the
magnitude of the force applied now if the force were applied for the duration of 5 second
what would be the final velocity of the object?​

Answer 1

Acceleration = Change in velocity/Time

                     = (7-3)/2 = 2m/s^2

Mass = 5kg

Force = Mass X Acceleration = 5 X 2 = 10N

Case 2

Force = 10N

Mass = 5kg

Acceleration = 2m/s^2

Now time = 5 seconds.

Change in velocity = Acceleration X Time

                               = 2 X 5 = 10m/s

Initial velocity =  3m/s

Change in velocity  = 10m/s

So, Final velocity = 3 + 10 = 13m/s

                Or

You can use the formula

v = u + at