physics
posted by Anonymous .
A(n) 4.5 lb hammer head, traveling at 4.7 ft/s
strikes a nail and is brought to a stop in
0.0009 s.
The acceleration of gravity is 32 ft/s
2
.
What force did the nail receive?
Answer in units of lb

Force * time = (hammer head momentum) = (mass)* (velocity)
The mass must be in slugs. Divide weight by g for slugs.
4.5 lb = 0.141 slugs
The force will be in pounds if velocity is in ft/s.