What does kepler's second law state? a. planets travel in ellipses. b. planets sweep equal areas in equal times. c. a planet's apparent backward movement is termed retrograde motion. d. an object's orbital period is related to its distance from the object it orbits.

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

How do we measure or think of speed in the united states?

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.