a cart accelerates from rest along a level track as a result of the action of a fan.  (a) Since the cart accelerates then according to Newton’s Second Law there must be a net horizontal force on it. What is the source of that force? Hints: (1)The fan cart unit cannot exert a force on itself, (2) What does Newton’s Third Law tell you?, (3) Would the fan cart unit accelerate if it were in outer space? (b) If friction is negligible identify the three forces acting on the cart and describe the direction of there forces relative the the coordinate system shown when the movie is opened in VideoPoint. (c)find the magnitude and direction of the acceleration of the cart in the horizontal direction. Explain how you determined the acceleration. Is it constant? How do you know? (d) What is the net work done on the cart as it travels from its location in frame 1 to its location in frame 14? What agent does this work?

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The cart accelerates from rest along a level track as a result of the action of a fan.

As the cart accelerates there is a force being applied on it. Newton's third law states that for every action there is an equal and opposite reaction. When the fan moves, a force is applied on the air and it accelerates in a direction away from the fan. The air moving out pushes the fan in the opposite direction with an equal force. The movement of the blades of the fan is able to push air as air is present on Earth. In outer space the fan cart unit would not accelerate as the blades of the fan would move in a similar fashion but there is no air that get pushed outwards.

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