Q1 Two particles, A and B, of mass 3 kg and 2 kg respectively, are joined by a light inextensible string which passes over a fixed, smooth pulley. Initially, both particles are held at rest with
particle A 60 cm higher than particle B. Both particles are then released from rest,
a) Draw a diagram showing the forces acting on the masses,
b) How long is it after the particles are released before they are level?

Stars x and y are both bluish main sequence stars. star x has a higher absolute brightness than star y. how do the two stars compare? explain

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?

Complete these sentences. if a roller coaster train has a potential energy of 1,500 j and a kinetic energy of 500 j as it starts to travel downhill, its total energy isj. once the roller coaster train gets closer to the bottom of the hill, its kinetic energy increases to 1,100 j, and its potential energy decreases to j. when the train reaches the bottom of the track and is traveling along the ground, its kinetic energy isj.