How Do You Calculate Work and Potential Energy in Physics Problems?

[hassanaw]

A 175 kg case must be loaded onto a truck that is 1.5m above the ground.
calculate work done

AND

An archer exerts a force of 100N as she draws the arrow back 0.60m.
what is the potential energy of the system before the string is released?
iam completely lost on these 2 questions we did this unit like a month ago, can somebody please help with full proper solutions?

thanks
tries:

w=fxd
=9.8x36
=353 Jfor question 2, i did
the Newtons =f
so = fxd
= answer

right formula?

 

[eczeno]

do you know how to calculate the work done by a constant force?

 

[rock.freak667]

Start with the definition of work done. What variables are in it?

 

[hassanaw]

w = f x d

f= m x a
force is mass times acceleration

d is displacement

 

[eczeno]

right, w = f x d. but be careful, if you are talking about the energy stored in the string, f needs to be the force of the string (not the person pulling it).

next, you need to know the relationship between potential energy and work.