Final answer:
An object's kinetic energy is determined by its mass and velocity, as defined by the formula KE = ½mv². A truck with greater mass moving at the same velocity as a lighter car will have more kinetic energy.
Step-by-step explanation:
What Determines an Object's Kinetic Energy?
The kinetic energy of an object is defined as the energy it possesses due to its motion. The formula for kinetic energy (KE) is KE = ½mv², where m represents the mass of the object and v the velocity at which the object is moving. Therefore, two main factors determine the kinetic energy of an object: its mass and its velocity.
For example, a truck with a mass of 2000 kg traveling at a velocity of 100 km/hr will have a significantly greater kinetic energy compared to a car weighing 500 kg at the same velocity. It's important to note that velocity is a relative measure, meaning the kinetic energy value depends on the frame of reference from which it is measured.
Kinetic energy is part of the total mechanical energy of a system, which is the sum of an object's kinetic and potential energies. While kinetic energy focuses on the motion of an object, potential energy relates to the position or state of an object. Together, they describe the full energy dynamics of a system.