Answer:
3 N to the right
Explanation:
There are two forces acting on the car:
- A force of 10 N towards the right
- A force of 7 N towards the left
Therefore, the net force is given by the difference between the two, since they are in opposite directions:
And the direction is to the right, since the force to the right has greater magnitude than the force to the left.
Answer: gravitational potential energy is converted into kinetic energy
Explanation:
When the diver stands on the platform, at 20 m above the surface of the water, he has some gravitational potential energy, which is given by
where m is the man's mass, g is the gravitational acceleration and h is the height above the water. As he jumps, the gravitational potential energy starts decreasing, because its height h above the water decreases, and he acquires kinetic energy, which is given by
where v is the speed of the diver, which is increasing. When he touches the water, all the initial gravitational potential energy has been converted into kinetic energy.