A ball of mass 0.3kg moving at a velocity of 20ms is suddenly hit by a force of 5N for a time of 0.03secs.find its new velocity of motion.

2 answers

force direction?
I bet you were told that Force is a vector.
It has magnitude AND direction.
Once you get that straightened out
net force on system = Force = rate of change of momentum of system
so if a system has a certain momentum
and a force acts on it for n seconds
the change in its momentum will be the force times the time
F t = change in m V