Difference between different kinds of motions of a rigid body

[avleen]

Hi
i want to know what the difference between general plane motion and rotation about fixed axis is?

im using their formulas for work and energy study and as far as i see their general equations are the same.

how do i identify which is which.

also in a disk with planar motion, is the instantaneous centre ALWAYS where the disk touches the ground?
please help!i have a specific example which is confusing me but it is an example in my book i don't know how to bring it up online so you guys can help me??
any suggestions?

 

[Doc Al]

i have a specific example which is confusing me but it is an example in my book i don't know how to bring it up online so you guys can help me??
any suggestions?

Maybe you can scan it and upload it. Or just describe it carefully.

 

[avleen]

Maybe you can scan it and upload it. Or just describe it carefully.

i will do that. but would you be able to explain the difference between the two motions?