Answer to Question #111183 in Mechanics | Relativity for dinsara

Question

If kinetic energy of an object is been same at all times, how does momentum of that object works?

Answer 1

The momentum of an isolated object is conserved. If the net force acting on an object is zero, then the linear momentum is constant. In an elastic collision (a superball hitting and rebounding from the ground), no kinetic energy is lost. All of that energy is still in the object, so one says that energy was conserved. If the kinetic energy did not change, then neither did the value of the momentum. (Momentum vector, however, changed, since the direction of momentum changed). Energy is a scalar, not a vector, so a direction change does not matter.

momentum of an isolated object (or system of objects) is conserved. If the net force acting on an object is zero, then the linear momentum is constant. In an elastic collision (such as a superball hitting and rebounding from the ground), no kinetic energy is lost. All of that energy is still in the object, so we say that energy was conserved. If the kinetic energy didn't change, then neither did the value of the momentum (The momentum vector, however, DID change, since the direction of momentum changed.). Energy is a scalar, not a vector, so a direction change doesn't matter.

Hence, If kinetic energy of an object has been same at all times, momentum too will remain unchanged.