Imagine that you are on mars, and you are swinging a pocket watch back and forth. you time the period of this simple pendulum to be 2.6 seconds, and you measure the chain on the pocket watch to be 63 centimeters. using this information, figure out what the gravity of mars is.

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.