Can any object have momentum even if its mechanical energy is zero? Explain.

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(NO) No,an object cannot have momentum if its mechanical energy is zero.
Mechanical energy is the sum of kinetic energy $(KE)$ and potential energy $(PE)$.
If the mechanical energy is zero,then $KE + PE = 0$.
Since kinetic energy $(KE = \frac{1}{2}mv^2)$ cannot be negative,and potential energy is typically defined relative to a reference point,for the total sum to be zero,both $KE$ and $PE$ must be zero.
If $KE = 0$,then $\frac{1}{2}mv^2 = 0$,which implies that the velocity $(v)$ of the object is $0$.
Since momentum $(p)$ is defined as the product of mass and velocity $(p = mv)$,if $v = 0$,then the momentum $(p)$ must also be $0$.

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