Can the kinetic energy of a system be negative?

[meredith]

what about the gravitational potential energy of a system?

Homework Statement

NA


2. Homework Equations
NA

 

[pimpalicous]

Nope. Think of the formula for KE. Mass is never negative, and even if the velocity is negative, its squared so the negative sign goes away.

Gravitational Potential can be negative depending on where you define your potential to be zero. But really, only changes in potential energy are relevant. Its only when the gravitational potential energy changes that the KE changes, a force is exerted, etc.

 

[thomate1]

3. The Attempt at a Solution
Yes, the kinetic energy of a system can be negative. This can occur when the system is losing energy, such as in a decelerating object. In this case, the kinetic energy would be negative because the object's velocity is decreasing. However, it is important to note that the total energy of the system, which includes both kinetic and potential energy, cannot be negative.

As for gravitational potential energy, it can also be negative depending on the reference point chosen. Gravitational potential energy is defined as the energy an object has due to its position in a gravitational field. If the reference point is chosen to be at a higher potential energy, then the gravitational potential energy of an object at a lower position would be negative. However, if the reference point is chosen to be at a lower potential energy, then the gravitational potential energy at a higher position would be positive. This is a convention used in calculations and does not affect the total energy of the system.