Kaplan Nursing Entrance Practice Exam

What does the formula 1/2 mv² represent?

1. Potential energy

2. Work done

3. Kinetic energy

4. Gravitational energy

The correct answer is: Kinetic energy

The formula 1/2 mv² represents kinetic energy, which is the energy an object possesses due to its motion. In this formula, "m" stands for the mass of the object and "v" represents its velocity. As the velocity increases, the kinetic energy increases exponentially, since velocity is squared in the equation. This relationship emphasizes how swiftly an object moves can significantly impact its kinetic energy. In contrast, potential energy pertains to the stored energy of an object based on its position, typically associated with gravitational potential energy depending on height and mass, which is represented by the formula mgh. Work done typically refers to the energy transferred when a force acts upon an object over a distance, expressed by the formula W = Fd, where W is work, F is force, and d is distance moved. Gravitational energy relates to the energy an object has due to its position relative to the Earth or another gravitational body, which is directly tied to mass and height above the ground. Understanding these distinctions helps clarify why the correct formula for kinetic energy is specifically 1/2 mv².