for an object in free fall, calculate the rate of change of the velocity from the first to the 100th second (metric units).

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?

I’ve been stuck on this for a while

(8%) problem 12. a bowling ball of mass mb 3 kg 's rolled down the lane with a velocity ofy-2/ m s lt strikes a single remaining pin mp 0.93 kg head on. after the collision the bowling ball has a velocity (in the same direction) of v2 1.1 m/s. = ▲ 33% part (a) write an expression for the velocity of pin in the horizontal direction after the impact, im ,, 33% part (b) what is the pins speed in ms? 33% part (c) assuming the coefficient of friction s μ,-0.1. how far in meters could the pin slide before stopping if it doesn't topple?