Answer:
4-mid ocean ridge at divergent plate boundaries.
The emerging velocity of the bullet is <u>71 m/s.</u>
The bullet of mass <em>m</em> moving with a velocity <em>u</em> has kinetic energy. When it pierces the block of wood, the block exerts a force of friction on the bullet. As the bullet passes through the block, work is done against the resistive forces exerted on the bullet by the block. This results in the reduction of the bullet's kinetic energy. The bullet has a speed <em>v</em> when it emerges from the block.
If the block exerts a resistive force <em>F</em> on the bullet and the thickness of the block is <em>x</em> then, the work done by the resistive force is given by,

This is equal to the change in the bullet's kinetic energy.

If the thickness of the block is reduced by one-half, the bullet emerges out with a velocity v<em>₁.</em>
Assuming the same resistive forces to act on the bullet,

Divide equation (2) by equation (1) and simplify for v<em>₁.</em>

Thus the speed of the bullet is 71 m/s
Answer:
When we see a region of a planet that is not as heavily cratered as other regions, it means that the surface of that region is younger.
Explanation:
There are a number of processes that affect planetary surfaces like erosion, volcanism, plate tectonics and the amount of craters by impact of meteorites.
The density of craters in a given region suggests the age of the surface. If the surface is saturated by craters then is likely very old because a long time should have passed for the planet to be hit by so many meteorites. If there are very few craters this may indicate that the surface is quite young, because the other processes described above wouldn't have had enough time to erase them. In any case we need to study the change of the cratering rate over time to determine the age of a given surface.
In collision type of problems since momentum is always conserved
we can say

So here along with this equation we also required one more equation for the restitution coefficient

so above two equations are required to find the velocity after collision
here the change in velocity occurs due to the contact force while they contact in each other
so this is the impulse of collision while they are in contact with each other while in collision which changes the velocity of two colliding objects
Answer:
19.2m/s
Explanation:
Assuming that 2.4m/s^2 was the acceleration and not a typo, we can use the equation v=at, where v=velocity, a=acceleration, and t=time,
plug in known varibles,
v=2.4*8
v=19.2m/s