Question

A 0.50kg object is at rest. A 3.00N force to the right acts on the objest during the time interval of 1.50s

Answer 1

The question you want to be answering is :
What is the velocity of the object at the end of this interval?

Key:
M=0.5kg
F=3N
Δt= 1.5s
Vi=0m/s

Formula:
F*Δt=m(Vf-Vi)

Plug it in
3(1.5)=0.5(Vf-0)

Solve for Vf
4.5=0.5Vf
Vf= 9 m/s