Aneutron star and a black hole are 3.34 x 1012 m from each other at a certain point in their orbit. the neutron star has a mass of 2.78×1030 kg and the black hole has a mass of 9.94×1030 kg. what is the magnitude of the gravitational attraction between the two?

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

2kg of refrigerant 134a undergoes a polytropic process in a piston-cylinder assembly from an initial state of saturated vapor at 2 bar to a final state of 12 bar, 80 degree c. a)determine the work for the process in kj. b)sketch the process on a p-v diagram.

We put a force of 50n on an object and the acceleration is 100 m/s². what is the mass of the object?