A 3.00 kg cart on a track is pulled by a string so that it accelerates at 2.00 m/s/s. The force of tension in the string is 10.0 N. What is the force of friction on the cart?

If the track is horizontal and the string is pulled horizontally, the friction on the cart would be .

Explanation:

Let denote the mass of this cart, and let denote the acceleration of this cart.

.

.

Apply Newton's Second Law to find the net force on this cart.

.

The following forces act upon this cart:

Assume that the track is horizontal, and that the string was pulled horizontally. The normal force from the track would exactly balance the downward gravitational attraction from the earth. Hence, the net force on this cart would be equal (in size) to the size of the tension from the string () minus the size of the friction from the track.

In other words:

.

.

.

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.