Multiple Choice Question

The motion of a satellite orbiting the Earth in a circular path at constant speed is a classic example of uniform circular motion. What property of this motion prevents its acceleration from being zero?

• A
  The total mechanical energy is conserved necessitating acceleration.
• B
  The direction of motion changes continuously at every point, meaning the velocity is changing.
• C
  The object's mass continually changes due to orbital dynamics.
• D
  The speed is too high for the gravitational force to sustain a constant velocity.