Brahe's concept of the planetary system was most like that of

ptolemy
copernicus
galileo
aristarchus

Aforklift raises a 1,020 n crate 3.50 m up to a shelf. how much work is done by the forklift on the crate? the forklift does j of work on the crate.

What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?

If the spring constant k of a pogo stick is 3500 n m and the weight of the person on the pogo stick is 700 n, how much is the spring in the botom of the pogo stick compressed?