What is the minimum work needed to push a car

[bosox3790]

What is the minimum work needed to push a 1025 kg car 200 m up along a 17.5° incline?

(a) Ignore friction.
I got 604117.9512J
(b) Assume the effective coefficient of friction retarding the car is 0.40?
how do I get this one?

 

[stunner5000pt]

for a) what does work do? What aspect of the car does it change? How do you calculate the work done then?

 

[bosox3790]

Do I need to know Work in this case?

 

[stunner5000pt]

Do I need to know Work in this case?

you can calculate work

work changes the energy

 

[Euclid]

Use the work-energy theorem:
$$W= \Delta K + \Delta U + |W_{fric}|$$
To find the minimum work, push the block slowly so that $$\Delta K=0$$. In (a), W_fric = 0. What is W_fric in (b)?