Work, Energy and Power for a Particle moving in a Potential Field

[Rongeet Banerjee]

Homework Statement

A particle with total Energy E is moving in a potential energy region U(x).Motion of the particle is restricted to the region when
1.U((x) greater than E
2.U(x) less than E
3.U(x) = E
4.U(x) less than or equal to E

Relevant Equations

Total Energy=Potential Energy+Kinetic Energy

But yet again my text says that option 4 is correct.

 

[PeroK]

It looks like you got option 4b there!

 

[Rongeet Banerjee]

Oh yes I corrected it.

 

[Rongeet Banerjee]

I don't understand that how can motion take place if U(x) becomes equal to E(x).KE in that case should be zero.So is the answer printed in my book wrong?

 

[PeroK]

I don't understand that how can motion take place if U(x) becomes equal to E(x).KE in that case should be zero.So is the answer printed in my book wrong?

A particle can stop! Think of a ball thrown up against gravity. It stops instantaneously and at that point its KE is zero.

 

[Rongeet Banerjee]

A particle can stop! Think of a ball thrown up against gravity. It stops instantaneously and at that point its KE is zero.

Oh so "motion of the particle is resticted to the region "meant that!Truly I am so humbled.