Question

A 5.00 kilogram mass is traveling at 100 meters per second. Determine the speed of the mass after an impulse of 30 Newton * seconds is applied.

Answer 1

Impulse is the change in momentum, J. It is measured in the same unit as momentum, kg•m/s or N•s
The formula for impulse is
J = ∆p = pf - pi
30Ns = pf - pi
pi = m*vi
pi = (5kg)(100m/s)
pi = 500kg-m/s
pf - 500kg-m/s = 30Ns
pf = 530kg-m/s
pf = m*vf
v f = pf /m
v f = (530kg-m/s)/(5kg)
v f = 106m/s (speed of the mass after an impulse)

Answer 2

Given: Mass m = 5.0 Kg; Initial Velocity Vi = 100 m/s

Impulse Ft = 30 N.s

Required: Final Velocity = ?

Formula: Ft = m(Vf -Vi)

Vf = Vi + Ft/m

Vf = 100 m/s + 30 N.s/5 Kg

Vf = 100 m/s + 6 m/s

Vf = 106 m/s