Calculating Work and Power: 50-N Force on a 2-kg Object

[zumi78878]

Homework Statement

65. A 50-N force is the only force on a 2-kg object that starts from rest. When the force has been
acting for 2 s the rate at which it is doing work is:
A. 75W
B. 100W
C. 1000W
D. 2500W
E. 5000W
ans: D

66. A 50-N force is the only force a 2-kg crate that starts from rest. At the instant the object has
gone 2m the rate at which the force is doing work is:
A. 2.5W
B. 25W
C. 75W
D. 100W
E. 500W

Q1 solved but i have no idea how to do the second one!

 

[CWatters]

Look up the standard equations of motion (SUVAT). Some are more useful for problems involving time (eg Q1) and others for displacement (Q2).

Perhaps this one...

V^2 = U^2 + 2as

where s = displacement