Answer:
K/2
Explanation:
The law of conservation of mechanical energy states that the sum of the kinetic and potential energies is a constant at any point.
At maximum height, the glove has purely potential energy but at the bottom, it has purely kinetic energy.
The potential energy at the top = kinetic energy at the bottom. The potential energy is given by
At half height, this potential energy is
At this height, PE + KE = Constant = KE at bottom or PE at maximum height.
Answer:
Explanation:
<u>Average Acceleration </u>
Acceleration is a physical magnitude defined as the change of velocity over time. When we have experimental data, we can compute it by calculating the slope of the line in velocity vs time graph.
Note: <em>We cannot see if the time axis is numbered in increments of 1 second, and we'll assume that. </em>
When , the graph shows a value of
When , the object is at rest,
We compute the average acceleration as
Answer:
a) 3.43 m/s
Explanation:
Due to the law of conservation of momentum, the total momentum of the bullet - rifle system must be conserved.
The total momentum before the bullet is shot is zero, because they are both at rest, so:
Instead the total momentum of the system after the shot is:
where:
m = 0.006 kg is the mass of the bullet
M = 1.4 kg is the mass of the rifle
v = 800 m/s is the velocity of the bullet
V is the recoil velocity of the rifle
The total momentum is conserved, therefore we can write:
Which means:
Solving for V, we can find the recoil velocity of the rifle:
where the negative sign indicates that the velocity is opposite to direction of the bullet: so the recoil speed is
a) 3.43 m/s