The Fan Cart Physics Gizmo shows a common teaching tool called a fan cart. Place fan A on the cart and turn it on by clicking the On/Off button below.

Question

1. Look at the blue lines coming from the fan. In which direction is the air pushed?

(1 point)

2. Press Play (Play) and observe the cart. In which direction does the cart move? (1 point)

By blowing to the left, the fans exert a force on the cart that pushes it to the right. This illustrates Newton’s third law: A force in one direction results in an equal force in the opposite direction.

3. The velocity (v) of the cart is its speed and direction. Click Reset (Reset). Select the BAR CHART tab, and click Play. Does the velocity change or stay the same? (1 point)

Answer 1

1. The blue lines coming from the fan indicate that the air is pushed in the direction opposite to the fan, which means the air is pushed to the left.

2. When you press Play and observe the cart, the cart moves to the right. This occurs because, as the fan blows air to the left, it exerts an equal and opposite force on the cart, causing it to accelerate to the right.

3. After clicking Reset and selecting the BAR CHART tab while clicking Play, the velocity of the cart changes as the fan continues to exert a force. The cart starts from rest and gains velocity in the direction of the force applied, indicating that the velocity of the cart increases.