Question

21 what energy conversion occurs in a cars engine?
thermal energy is converted into gravitational potential energy.
gravitational potential energy is converted into electrical potential energy.
kinetic energy is converted into elastic potential energy.
chemical potential energy is converted into thermal energy.

Explanation:

A car's engine uses fuel (like gasoline), which has chemical potential energy. When the fuel burns in the engine, this chemical potential energy is converted into thermal energy (heat) as part of the combustion process, and then further into mechanical energy to move the car. Let's analyze each option:

• The first option is incorrect because thermal energy from the engine isn't converted to gravitational potential energy (which is related to height, not car engines).
• The second option is wrong as gravitational potential energy (related to position in a gravitational field) isn't converted to electrical potential energy in a car engine's main energy conversion.
• The third option is incorrect because kinetic energy (energy of motion) isn't converted to elastic potential energy (energy in stretched/compressed objects) in a car engine's primary energy conversion.
• The fourth option is correct: the chemical potential energy in the fuel is converted into thermal energy during combustion in the engine.

Answer:

Chemical potential energy is converted into thermal energy.