Final answer:
Kinetic energy is the energy of an object due to its motion, calculated using the formula KE = 1/2mv², where m is mass and v is velocity squared. It's a key concept in physics, proportional to the mass and the square of the velocity, with energy measured in joules.
Step-by-step explanation:
Kinetic Energy
The concept of kinetic energy is a fundamental principle in Physics. It is typically defined as the energy that an object possesses due to its motion. The correct formula to calculate an object's kinetic energy (KE) is KE = 1/2mv², where m represents the mass of the object and v represents the speed (or velocity) of the object, squared. This equation implies that the kinetic energy of an object is directly proportional to its mass and the square of its velocity. For example, an object with a mass of 2 kg moving at a velocity of 3 m/s would have a kinetic energy of 9 J (joules), since KE = 1/2 × 2 kg × (3 m/s)² = 1 kg × 9 m²/s² = 9 J.
Energy in physics is generally described as the capacity to do work or produce heat, and the SI unit for measuring energy is the joule (J). The concept of kinetic energy helps explain why, for instance, collisions at higher speeds can be much more destructive than those at lower speeds, due to the quadrupling of kinetic energy when the speed is doubled. A car traveling at 100 km/h, for example, has four times the kinetic energy it would at 50 km/h.