Consider a one-dimensional motion of a particle with total energy E. There are four regions A, B, C and D in which the relation between potential energy V, kinetic energy K and total energy E is as given below:
Region A:V gt E
Region B: V lt E
Region C:K gt E
Region D:V gt K
Which of the following regions the particle cannot be found?

Explanation

A particle cannot be found in the given region when `KEltO`.
We know that
Total energy `E=PE+KE`
`impliesE=U+K`
For region A Given `UgtE` from Eq. (i)
`K=E-U`
as `UgtEimpliesE-Ult0`
Hence `Klt0`, this is not possible. For region B Given, `UltEimpliesE-Ugt0`
This is possible because total energy can be greater tan PE (U).
For region C Given, `KgtEimpliesK_Egt0`
From Eq. (i) `PE=U=E-Klt0`
Which is possible because PE can be negative.
For region D Given, `UgtK`
This is possible because for a system PE(U) may be greater than KE(K).