The person walking down the sidewalk follows the newton's third law of motion.
Explanation:
- A person is able to walk down the sidewalk by using the reaction forces from the ground.
- In simple term, feet pushes the ground and the reaction forces makes the feet able to walk.
- Another important force included in the walking mechanism is friction. With out friction one cannot walk down the sidewalks.
- Hence the forces involved in the walking of a person down the sidewalk are:
- Friction force
- Action and reaction force between ground and person's feet.
The amount of solid does not affect how you are describing the solid so a is the answer
Kinetic energy = 1/2 * mass * velocity^2
In this case,
KE = 1/2 * 1569 kg * (15 (m/s))^2 = 176,5 kN
Mass (kg) = force (N) / acceleration (m/s).
200/2.5 = 80
