Question

John has tied his friend, Zory, a stuffed unicorn to a toy car with a massless string whichmakes an angle of 30°. If he rides for 20 m. The weight of the unicorn is 50 N. The toy car exerts a constant force of 20 N and there is a frictional force of 10 N.
a. Find the work done on the unicorn by each forces.
b. Find the net work done on the unicorn.
c. If the initial velocity was 2m/s, what will be the final velocity?

Answer 1

Answer: A

Since the car is moving to the right, the Normal Force is balancing the Weight and the Net Force is 10 N, right.

Explanation:

as the answers says, the only two forces in the y axis are the normal force and the weight, and they balance each other. On the x axis, you have 20N to the right and the friction is a force that opposes the movement, so the 10N are to the left. The net force is 20 - 10 = 10N.