Asatellite moves around the earth in a circular orbit of radius r. what is the speed vi of the satellite?

Yvette hangs a 2.4kg bird feeder in the middle of a rope tied between two trees. the feeder creates a tension of 480 n in each side of the the rope.

On mars a rock falls an unknown vertical distance from a resting position and lands in a crater. if it takes the rock 2.5 seconds to fall, how high is the cliff the rock fell from? mars' surface gravity is 3.8 m/s2. a. 9.5 m b. 11.9 m c. 15.2 m d. 23.8 m

Relative to the ground below, how many joules of potential energy does a 1000-kg boulder have at the top of a 5-m ledge?