Rotational doubt (also momentum)

1. Dec 11, 2008

iitjee10

If a ball collides elastically with a stick at a point other than its centre of mass, then can we use coefficient of restitution is one or do we have to use initial kinetic energy = final kinetic energy??

If we can't use "coefficient of restitution is one" then why???

2. Dec 11, 2008

Staff: Mentor

According to the definition of an elastic collision, the total kinetic energy is conserved.

3. Dec 11, 2008

iitjee10

so u r telling that we cant use coefficient of restitution as zero in this case??

4. Dec 11, 2008

clem

You must mean one instead of zero.
The COF will not be one if either object starts to rotate.

5. Dec 12, 2008

iitjee10

Yeah i meant 1
then what will be COR??

6. Dec 12, 2008

Staff: Mentor

Why not forget about COR and just apply conservation of linear momentum, angular momentum, and kinetic energy.