Force MCQ Practice_13

An Earth satellite moves in a circular orbit 5000 km above the Earth’s surface. The period of the motion is 212 minutes. What is the acceleration of the satellite? The Earth’s radius is 6,378,140 m.

A bob of mass 0.5 kg is suspended from the end of a piece of string 0.45 m long. The bob is rotated in a vertical circle at a constant rate of 120 revolutions per minute. What is the magnitude of the tension in the string when the bob is at the bottom of the circle?

Planet 1 orbits Star 1 and Planet 2 orbits Star 2 in circular orbits of the same radius. However, the orbital period of Planet 1 is longer than the orbital period of Planet 2. What could explain this?
A) Star 1 has less mass than Star 2.
B) Star 1 has more mass than Star 2.
C) Planet 1 has less mass than Planet 2.
D) Planet 1 has more mass than Planet 2.
E) The masses of the planets are much less than the masses of the starts.

A mass m = 4.7 kg is suspended from a string. It revolves in a horizontal circle of radius 86 cm. The tangential speed of the mass is 2.97 m/s. What is the angle θ between the string and the vertical?