Conservation of energy Study Guide

Efficiency is a measure of how effectively an energy transfer device converts the total energy supplied into useful energy. No device is 100% efficient due to energy losses, often as heat or sound, to the surroundings. The efficiency equation quantifies this relationship as the ratio of useful energy output to total energy input, typically expressed as a percentage or a decimal. A higher efficiency value means less energy is wasted during the transfer process.

Gravitational potential energy (GPE) is the energy an object possesses due to its position in a gravitational field. When an object is lifted or raised to a certain height above a reference point (often the ground), work is done against gravity, and this work is stored as an increase in its GPE. Conversely, if an object falls, its GPE decreases, and this energy is typically converted into other forms, such as kinetic energy. The change in gravitational potential energy is directly proportional to the object's mass, the strength of the gravitational field, and the change in its vertical height. This relationship is crucial for understanding energy transformations in many physical scenarios.