A horizontal force of 2.0 N is applied to a 1.5 kg cart on a horizontal surface. The coefficient of friction is 0.55. What is the acceleration of the cart given that the cart was originally moving?

To find the acceleration of the cart, we need to calculate the net force acting on it. The net force is the difference between the applied force and the force of friction.

The force of friction can be calculated using the equation:
Frictional force = coefficient of friction × normal force

The normal force is equal to the weight of the cart, which can be calculated as:
Weight = mass × acceleration due to gravity

Once we have the force of friction, we can find the net force by subtracting it from the applied force.

Finally, we can use Newton's second law of motion to calculate the acceleration:
Net force = mass × acceleration

Let's go through the calculations step by step.

1. Calculate the weight of the cart:
Weight = mass × acceleration due to gravity
Weight = 1.5 kg × 9.8 m/s^2
Weight = 14.7 N

2. Calculate the force of friction:
Frictional force = coefficient of friction × normal force
Frictional force = 0.55 × 14.7 N
Frictional force = 8.08 N

3. Calculate the net force:
Net force = applied force - force of friction
Net force = 2.0 N - 8.08 N
Net force = -6.08 N

Note: The negative sign in the net force indicates that the force is acting in the opposite direction of motion, which means the cart is slowing down.

4. Calculate the acceleration:
Net force = mass × acceleration
-6.08 N = 1.5 kg × acceleration
acceleration = -4.05 m/s^2

The acceleration of the cart is -4.05 m/s^2.