Energy and Electrical Devices

This is the correct answer. Electrical energy can be changed into mechanical (moving a machine part), sound (loudspeaker) and magnetic energy (electromagnet).

This is the correct answer. Electric energy is converted into both, heat and light energy, in an electric bulb.

This is the correct answer. Sliding switch acts as a switch in circuit, which can open and close a circuit.

A wound-up watch spring stores energy due to its position or configuration, which is the definition of potential energy (specifically elastic potential energy).

The internal combustion engine and modern engine technology were revolutionized by the discovery and refinement of petroleum as a fuel source.

Electromagnetic induction is the principle behind the operation of electric generators, where mechanical energy is converted into electrical energy.

An LED (Light Emitting Diode) is a semiconductor device that emits light when current passes through it, often used as an indicator light.

Chemical energy of food is used in respiration to produce oxygen.

A UPS (Uninterruptible Power Supply) provides battery backup to keep the computer running during a power failure. Batteries are components, but UPS is the specific device.

An Uninterruptible Power Supply (UPS) provides battery backup power to a computer when the main electricity supply fails, allowing for a safe shutdown.

Cryogenic engines use liquid propellants at extremely low temperatures and are essential for modern rocket propulsion systems.

CFCs were historically used as refrigerants in refrigerators and air conditioners before being phased out due to their role in ozone depletion.

The spring wound in watch is strained. Hence the energy is Potential.

This is the correct option. The household appliance, which is not having an element is an electric bell.