A student drops a rubber ball onto a surface. Assume that this is a closed system. The ball bounces, but each successive bounce
is shorter than the one before it. Eventually, the ball comes to a stop. Which statement provides evidence that supports the idea that energy is conserved in this closed system?
A. The ball moves through air, suggesting that the ball has mechanical energy.
B. The ball needs a push or pull to start moving, suggesting it needs a constant input of energy.
C. The ball makes a sound with each bounce, suggesting that some kinetic energy transformed into sound.
D. The ball bounces many times, suggesting the energy is used up efficiently
A. The ball moves through air, suggesting that the ball has mechanical energy.
B. The ball needs a push or pull to start moving, suggesting it needs a constant input of energy.
C. The ball makes a sound with each bounce, suggesting that some kinetic energy transformed into sound.
D. The ball bounces many times, suggesting the energy is used up efficiently
2 answers:
You might be interested in
Answer:
68cm
Explanation:
You can solve this problem by using the momentum conservation and energy conservation. By using the conservation of the momentum you get
m: mass of the bullet
M: mass of the pendulum
v1: velocity of the bullet = 410m/s
v2: velocity of the pendulum =0m/s
v: velocity of both bullet ad pendulum joint
By replacing you can find v:
this value of v is used as the velocity of the total kinetic energy of the block of pendulum and bullet. This energy equals the potential energy for the maximum height reached by the block:
g: 9.8/s^2
h: height
By doing h the subject of the equation and replacing you obtain:
hence, the heigth is 68cm
Answer:
a). 53.75 N and 101.92 N
b). 381.44 N and 723.25 N
Explanation:
a).
ρ,
,
b).
ρ,
,