Question

While the cart is moving along an aisle, it comes in contact with a smear of margarine that had recently been dropped on the floor. Suddenly the friction force is reduced for -40.0 newtons to -20.0 newtons. What is the net force on the cart if the "pushing force" remains at 40.0 newtons? Does the grocery cart move at constant velocity over the spilled maragine?

Answer 1

The net force on the cart is 60.0 N and the grocery cart will not move at a constant velocity.

Step-by-step explanation:

The net force on the cart can be found by subtracting the friction force from the pushing force.The grocery cart will not move at a constant velocity over the spilled margarine. The net force is now 60.0 N, which means there is an unbalanced force acting on the cart. The cart will either accelerate or decelerate depending on the direction of the net force. Since the friction force is reduced from -40.0 N to -20.0 N, the net force on the cart is

Net force = Pushing force - Friction force

Net force = 40.0 N - (-20.0 N)

Net force = 60.0 N

The grocery cart will not move at a constant velocity over the spilled margarine. The net force is now 60.0 N, which means there is an unbalanced force acting on the cart. The cart will either accelerate or decelerate depending on the direction of the net force.

Answer 2

No, the velocity of the grocery cart will not remain constant, but instead will increase continuously

Step-by-step explanation:

No the grocery cart will not move at constant velocity over the spilled maragine because as the frictional force is changed to - 20 N, the net force will not be equal to zero

Net force on the cart when frictional force is changed to - 20 N is 40 - 20 N = 20 N

As the force is positive, it means that the force is acting in the direction of motion of the cart and will increase the velocity of the cart as the force is acting in the direction of motion

∴ The velocity of the cart will not remain constant instead it will increase