Answer:
80 ft/s
Explanation:
Use III equation of motion
V^2 = U^2 + 2g h
Here, U = 0, g = 32 ft/s^2, h = 100 ft
V^2 = 0 + 2 × 32 ×100
V^2 = 6400
V = 80 ft/s
Answer:
122.5 N/m
Explanation:
According to the law of conservation of energy, if there is no air resistance or frictional forces, the initial elastic potential energy of the spring toy is entirely converted into gravitational potential energy when the toy reaches the highest point.
Therefore, we can write:

where the term on the left is the initial elastic potential energy while the term on the right is the gravitational potential energy, and where
k is the spring constant
x = 0.02 m is the compression of the spring
m = 0.01 kg is the mass of the toy
h = 0.25 m is the height reached by the toy
is the acceleration due to gravity
Solving for k,

Answer:
200 N
Explanation:
Given that,
A ball traveling at 15 m/s hits a bat with a force of 200 N.
We need to find the force that the bat moving at 20 m/s hit the ball with.
We know that, this probelm is based on Newton's third law of motion. The force that the ball exerting on bat should be equal to the force that the bat exerting in the ball but in opposite direction.
It would mean that the ball hits the ball with a force of 200 N. Hence, the correct option is (a).
Answer: Point A is the answer for the potential energy. Point D is the answer for the kinetic energy.
Explanation: