We started our class with a problem. We had 3 senerios. A box being lifted by a crane, a box at the top of a frictionless surface sliding down the ramp, and a box being pushed up a frictionless ramp. A and B are the same because they have the same amount of displacement. To convert grams to kilograms you divide it by 1000 because there are 1000 grams in a kilogram. To find the force of a 20 kg object you multiply by 100 and get 200N. To get it up a 2m high ramp it takes 400J because you have to multiply by the hight of the ramp,(2m.)by the force it takes to move the object
(200N). The differnce between force and work is it takes alot of muscle to exert force and no work can be done.