The law of conservation of momentum basically means that energy is always conserved and never lost when a collision happens.
Using the formula p=mv ...
Player A would have a momentum of 220 N•S
Player B would have a momentum of 0 because he is not moving
After the collision, the total momentum is still 220 N•S because energy is never lost, but now player A is at 0 and player B took his momentum. Think about it this way, if you bumped into something that wasn’t moving, it would fall and you most likely wouldn’t keep moving.
Elastic collisions are where the objects bounce each other and in inelastic collisions they stick together. I don’t watch much football but if you do this should make sense.
If the players fall down together (they tackle each other and fall? I think) it should be inelastic.
Sorry if this was long and confusing but I really hope this helps! ☺️
Answer:
C. pressure
because heat expands and so does explosions and gravity is just gravity.
The velocity of the ball when it reaches the ground is equal to B. 68.6 m/s. This value was obtained from the formula Vf = Vi + at. Vf is the final velocity. Vi is the initial velocity. The acceleration is "a", while the time of travel is "t". The solution is:
<span>Vf = Vi + at
</span>Vf = 0 + (-9.8 m/s^2) (7 s)
Vf = -68.6 m/s
The negative sign denotes the direction of the ball.
By looking at the acceleration of the object.
In fact, Netwon's second law states that the resultant of the forces acting on an object is equal to the product between the mass m of the object and its acceleration:

So, when static friction is acting on the object, if the object is still not moving we know that all the forces are balanced: in fact, since the object is stationary, its acceleration is zero, and so the resultant of the forces (left term in the formula) must be zero as well (i.e. the forces are balanced).