Two equally massive spheres are spaced 2 meters apart. The gravitational attraction between them is 4.62 E 10 N. The gravitational constant G is equal to 6.67 E -11 N*m2/kg2. What is the mass of each sphere?

Aproton is projected toward a fixed nucleus of charge +ze with velocity vo. initially the two particles are very far apart. when the proton is a distance r from the nucleus its velocity has decreased to 1/2vo. how far from the nucleus will the proton be when its velocity has dropped to 1/4vo?

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds

Acar moves at 12m/s and coasts up a hill with a uniform acceleration of -1.6m/s2. how far has it traveled after 6.0s?