Can the kinetic energy of an object be negative? Can the potential energy be negative?

(N/A) The kinetic energy $(K = \frac{1}{2}mv^2)$ of an object can never be negative. Since mass $(m)$ is always positive and the square of velocity $(v^2)$ is always non-negative,the kinetic energy must be $\ge 0$.
Potential energy $(U)$ can be negative. Potential energy is defined relative to a reference point where $U = 0$. For example,in a gravitational field,if we choose the reference point at infinity,the gravitational potential energy of a system is negative.