What will happen to the rotational motion

In summary, the direction of translational motion will be reversed in a collision with a wall, assuming the wall is perfectly elastic and does not fail upon impact. However, the rotational motion will depend on the friction of the wall. If there is no friction, the ball will go back in the opposite direction with the same spin. If there is friction, the ball will slightly change direction and its rotation will slow down slightly. To completely reverse the rotational motion, the wall would need to impart an angular impulse equal to the magnitude of the ball's initial spin in the opposite direction, which is not physically possible to replicate.
  • #1
nishant
95
0
if a body is rotating forward towards a wall,colides with the wall ofcourse the direction of motion will be reversed,,but what will happen to the rotational motion,if it is given that the infinitely rough
 
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  • #2
Did you stop in the middle of a sentence? Acutally "of course the direction of motion will be reversed" is not "of course" at all. If there is no friction (and the collision is perfectly elastic) then the body would go back in exactly the opposite direction with exactly the same spin. If there is friction however (I don't think it needs to be "infinitely rough"!) The ball exerts some force on the wall in one direction and so will not go straight back but slightly of to one side while its rotation slows slightly. What "slightly" is depends upon the friction.
 
  • #3
The translational motion (not rotation) will be reverse if the wall is perfectly elastic and will not fail upon impact. The rotation will change depending on the friction of the wall. The range of rotational change will be from a rotation that is slightly slowing down to a rotation of opposite spin with the same magnitude. The same magnitude requires ideal conditions which you can figure out because I will probably leave some assumptions out. Can someone list all the ideal conditions for the translational and rotational motion to be reversed upon impact of the wall?
 
  • #4
Translational motion is conserved in a perfectly elastic frictionless collision.
Rotational is another thing though. For the rotational to be stopped, the wall would need to impart an angular impulse such that its magnitude is exactly that of the spinning ball (and opposite direction). If this is done in an infinitely small time period (to maintain the elastic requirement) the ball will lose all its rotational motion. An example is if you threw it at something like a conveyor belt. To reverse the motion with the same magnitude, your angular impulse would need to be twice as strong as the initial angular momentum of the ball.

Ofcourse these are idealistic, and not physically possible to replicate.
 

Related to What will happen to the rotational motion

What is rotational motion?

Rotational motion is the movement of an object around an axis or center point.

What factors affect rotational motion?

The factors that affect rotational motion include the mass of the object, the distribution of mass, and the force or torque applied to the object.

What is the difference between linear and rotational motion?

Linear motion is movement in a straight line, while rotational motion is movement around an axis. Linear motion can be described by displacement, velocity, and acceleration, while rotational motion can be described by angular displacement, angular velocity, and angular acceleration.

What is angular momentum and how does it relate to rotational motion?

Angular momentum is a measure of an object's tendency to continue rotating at a constant rate. It is equal to the product of the object's moment of inertia and its angular velocity. In rotational motion, angular momentum is conserved if there is no external torque acting on the object.

What are some real-world examples of rotational motion?

Some examples of rotational motion include the spinning of a top, the rotation of a wheel on an axle, the swinging of a pendulum, and the spinning of the Earth on its axis.

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