A man pushed the box with a force of 20 N. He doubled his force to 40 N. The box did not change. Which option best describes the acceleration of the box after the force was doubled?

a) Acceleration is 2x the original acceleration

b) Acceleration is 4x the original acceleration

c) Acceleration is 1/2x the original acceleration

d) Acceleration is 1/4x the original acceleration

On a frictionless air track, a blue glider with mass 0.200 kg is moving to the right with a speed of 8.00 m/s. it strikes a red glider that has mass 0.600 kg and that is initially at rest. after the collision, the blue glider is moving to the left with a speed of 3.00 m/s.(a) what are the magnitude and direction of the velocity of the red glider after the collision? (b) is this collision elastic?