What is gravity?(20 points) 1. A force that pulls objects toward the center of Earth.

2. A force that pushes objects away from the center of Earth.

3. Energy that moves objects away from the center of Earth.

4. Energy that moves objects toward the center of Earth.

Awind turbine is rotating counterclockwise at 0.5 rev/s and slows to a stop in 10 s. its blades are 20 m in length. (a) what is the angular acceleration of the turbine? (b) what is the centripetal acceleration of the tip of the blades at t=0s? (c) what is the magnitude and direction of the total linear acceleration of the tip of the blades at t=0s?