Respuesta :
Answer:
Statements 4, 6 & 7 are false.
Explanation:
For any elastic collision the vector sum of the total momentum of the system is zero.
Here we have an elastic collision between the ball and a fixed wall. The velocity of the ball will always remain zero whereas the velocity (hence momentum) of the ball will totally revert after the collision.
Initial momentum of the ball is given as:
[tex]p=m.v[/tex]
where:
m = mass of the ball
v = initial velocity of the body
after the elastic collision:
[tex]p=m.(-v)[/tex]
- Here the direction of the velocity is reversed, hence the momentum is changed only in terms of direction violates the statement 7.
- At the moment of collision the ball and the wall exert an equal and opposite force mutually on each other. The wall does not moves in any case whereas the ball moves in the direction of the reaction force of the wall hence it does some work on the ball violating the statement 4.
- Since the collision is elastic the shape and size of the ball remains intact.
- From the above explanation it is clear that that not all the given statements are correct hence statement 6 goes violated.
.4. the wall does no net work on the ball.
.6. All of these statements are true.
7. The ball's momentum is unchanged by the collision
Effect of work and momentum on the ball
The wall does work on the ball when the ball strikes with the wall due to reaction of the wall. The ball's momentum is changed by the collision because some of the energy is transformed into other forms.
So we can conclude that option 4, 6 and 7 are false.
Learen more about collision here: https://brainly.com/question/7538238
