Elastic Collision Problem - pretty sure my answer isn't right.

In summary, the problem involves two bumper cars colliding with different masses and velocities. Using the equation for conservation of kinetic energy, the final speed of Wolfie after being hit by Walt from the rear is found to be 4.17 m/s, which may seem unreasonable since it is higher than Walt's initial velocity. However, this is due to the fact that Wolfie is less massive than Walt, and the kinetic energy of the bumper cars themselves must also be taken into account.
  • #1
gh_pluvilias
8
0

Homework Statement


Walt and Wolfie collide in bumper cars of mass 50 kg each. Walt has a mass of 78 kg, and Wolfie has a mass of 61 kg. Walt strikes Wolfie from the rear at V = 3.7 m/s. If the collision is elastic, Wolfie is initially at rest, and Walt's final speed is 0.2655 m/s in the same direction, what is Wolfie's speed after the collision?


Homework Equations


m1*(u1^2)/2 = m1*(v1^2)/2 + m2*(v2^2)/2


The Attempt at a Solution


78*(3.7^2)/2 = 78*(0.2655^2)/2 + 61*(x^2)/2
and I get 4.17 m/s, but that doesn't seem right to me.
Can anyone shed some light on this for me?
 
Physics news on Phys.org
  • #2
Why doesn't 4.17 m/s sound reasonable to you?
 
  • #3
Then Wolfie's speed after the collision is higher than the velocity that Walt hit Wolfie with initially, which doesn't seem right.
 
  • #4
What happened to the mass of the bumper cars themselves?
 
  • #5
Along SteamKing's lines, remember that the bumper cars are part of the kinetic energies we're talking about. With that said, Wolfie is less massive that Walt, so might it be conceivable that he's going faster than Walt was? We're talking about energy conservation, not velocity conservation.
 

FAQ: Elastic Collision Problem - pretty sure my answer isn't right.

What is an elastic collision?

An elastic collision is a type of collision between two objects in which there is no loss of kinetic energy. This means that the total kinetic energy of the objects before and after the collision remains the same.

How is the velocity of the objects calculated after an elastic collision?

The velocity of the objects after an elastic collision can be calculated using the conservation of momentum and the conservation of kinetic energy equations. These equations take into account the mass and velocity of the objects before and after the collision.

What is the difference between an elastic collision and an inelastic collision?

In an elastic collision, there is no loss of kinetic energy, while in an inelastic collision, some of the kinetic energy is converted into other forms of energy, such as heat or sound. This means that the total kinetic energy of the objects in an inelastic collision will be less than the total kinetic energy before the collision.

Can an elastic collision occur between two objects of different masses?

Yes, an elastic collision can occur between two objects of different masses. The conservation of momentum and the conservation of kinetic energy equations take into account the masses of the objects, so the velocities of the objects after the collision will depend on their masses.

What are some real-life examples of elastic collisions?

Some real-life examples of elastic collisions include billiard balls colliding on a pool table, a game of ping pong, and a rubber ball bouncing off a hard surface. These collisions exhibit no loss of kinetic energy and the objects involved bounce off each other at the same speed they had before the collision.

Similar threads

Replies
9
Views
12K
Replies
16
Views
3K
Replies
5
Views
2K
Replies
22
Views
3K
Replies
8
Views
2K
Replies
4
Views
4K
Replies
15
Views
2K
Replies
4
Views
1K
Replies
3
Views
1K
Back
Top