Consider a one-dimensional motion of a particle with total energy E. There are four regions A, B, C and D is which the relation between potential energy U, kinetic energy (K) and total energy E is as given below
RegionA: `UgtE` Region B: `UltE`
Region C: `KltE` Region D: `UgtE`
State with reason in each case whether a particle can be found in the given region or not.

Explanation

As is known, `E=K+V`, where `K` is always positive but `V` can be positive or negative.
In Region A. `V gt E ` As `K=E-V :. K` is negative, which is not permissible.
In Region B. `V lt E` or `E gt V` i.e total energy is greater than PE. `:. ` Particle can be found in region `B` .
In Region `C`. `K gt E`, which is possible when `V` is negtive. `:.` Particle can be found in region `C`.
In Region `D`. `V gt K` i.e. `PE gt KE` ehich is allowed.
Hence particle can be found in region D.