Aball is rolling down a hill at +2.0 m/s. the ball is uniformly accelerating at 4.0 m/s^2. what will the balls velocity be 3.0 s later?
a. 10
b. 5.3
c. 14
d. 13

How many neutrons does element x if it’s atomic number is 28 and its mass number is 87

Acoil suspended freely, points in some direction when no current is passed through it . can you tell what will happen when a current is passed though it?

Two identical stars with mass m orbit around their center of mass. each orbit is circular and has radius r, so that the two stars are always on opposite sides of the circle. (a) find the gravitational force of one star on the other. (b) find the orbital speed of each star and the period of the orbit. (c) how much energy would be required to separate the two stars to infinity?