What are the main forms of energy, and give an example of an energy transformation.

• A. Forms: kinetic and potential energy. Example transformation: chemical energy in glucose to kinetic energy in muscle.
• B. Forms: thermal and electrical energy. Example transformation: wind to solar.
• C. Forms: sound and light energy. Example transformation: sound to kinetic.
• D. Forms: gravitational and magnetic energy. Example transformation: magnetic energy to kinetic.

Answer: (A)

Energy exists in different forms and can be transformed from one form to another. Two fundamental forms often taught are kinetic energy, the energy of motion, and potential energy, stored due to position or configuration. The example given shows chemical energy stored in glucose being converted into kinetic energy as muscles contract to move a limb. This clearly illustrates turning stored chemical energy into mechanical work, with some energy typically ending up as heat due to inefficiency.

The other options mix different energy types or present a transformation that isn’t a straightforward single-step change between the main forms, so they don’t illustrate the basic idea as cleanly.