Let's first consider the dynamics behind the motion in this video. After the student releases the wheel by cutting the cord, what forces are acting on the wheel

Hello. You did not provide the video to which the question refers, however, given the context of your question, we can consider that the forces acting on the wheel are the weight of the wheel, the tension that this weight promotes on the rope and the normal force of the axle.

Explanation:

According to the context of the question, we can see that the wheel is being pulled by a rope. The weight of the wheel is the first force that acts on it, promoting resistance to the impulse that the rope promotes on the wheel. When this wheel is pulled by the rope, the weight of the wheel creates tension in the rope, which stretches and becomes tensioned in response to this force. However, this tension is also a force acting on the wheel, as is the normal force on the axis between these two elements.

no link

explanation:

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.