What is the total net force and in what direction?

How much work would be needed to raise the payload from the surface of the moon (i. e., x = r) to an altitude of 5r miles above the surface of the moon (i. e., x = 6r)?

The two stars in a certain binary star system move in circular orbits. the first star, alpha, has an orbital speed of 36 km/s. the second star, beta, has an orbital speed of 12 km/s. the orbital period is 137 d. a) what is the mass of the star alpha? b) what is the mass of the star beta?

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?