In an electric circuit, what energy source transforms into mechanical motion?

The correct answer is chemical energy because it is the type of energy that is typically stored in batteries and fuels. In an electric circuit, when a battery provides power, the chemical energy within it is converted into electrical energy. This electrical energy can then drive motors that convert it into mechanical motion.

For example, in a battery-powered toy or an electric car, the chemical reactions within the battery release energy that is used to create motion through an electric motor. This is a fundamental process in many electric devices, where the transformation from chemical energy to electrical energy and finally to mechanical energy is essential for the operation of the device.

The other types of energy mentioned, such as thermal energy, gravitational energy, and elastic energy, do not directly convert into mechanical motion in the context of an electric circuit. Thermal energy typically results from heat rather than direct mechanical work, gravitational energy relates to the potential energy of an object in a gravitational field, and elastic energy is stored in materials when they are deformed. While these forms of energy can lead to motion under certain conditions, they are not the primary energy source transforming into mechanical motion in electric circuits.