Question

you did 150 joules of work lifting a 120 newton backpack
a) How high did you lift the backpack?
b)How much did the back pack weigh in pounds ? (Hint - 4.448 newtons)

Answer 1

That is pretty simple..... see W=Fh ... here w= work done; F= force and h=height!
We know W ; F  so we can easily calculate height...150=120h ...h=1.25!
It weighs 26 pounds!