downward force then reaction if you mean what forces
Answer:
When you jump down, your kinetic is converted to potential energy of the stretched trampoline. The trampoline's potential energy is converted into kinetic energy, which is transferred to you, making you bounce up. At the top of your jump, all your kinetic energy has been converted into potential energy. Right before you hit the trampoline, all of your potential energy has been converted back into kinetic energy. As you jump up and down your kinetic energy increases and decrease.
Answer:
Part a)

Part b)
v = 3.64 m/s
Part c)

Part d)

Explanation:
As we know that moment of inertia of hollow sphere is given as

here we know that

R = 0.200 m
now we have


now we know that total Kinetic energy is given as





Part a)
Now initial rotational kinetic energy is given as



Part b)
speed of the sphere is given as
v = 3.64 m/s
Part c)
By energy conservation of the rolling sphere we can say




Part d)
Now we know that




Answer:
h> 2R
Explanation:
For this exercise let's use the conservation of energy relations
starting point. Before releasing the ball
Em₀ = U = m g h
Final point. In the highest part of the loop
Em_f = K + U = ½ m v² + ½ I w² + m g (2R)
where R is the radius of the curl, we are considering the ball as a point body.
I = m R²
v = w R
we substitute
Em_f = ½ m v² + ½ m R² (v/R) ² + 2 m g R
em_f = m v² + 2 m g R
Energy is conserved
Emo = Em_f
mgh = m v² + 2m g R
h = v² / g + 2R
The lowest velocity that the ball can have at the top of the loop is v> 0
h> 2R
Force is the change in momentum over a specific time. The change of momentum is therefore the force multiplied by the time that the force acts, so 3000x4.0=12000 N s=12000 kg m/s