Energy conversions

Energy Conversions

​A pendulum swinging back and forth would be converting between potential and kinetic energy.

​Elastice Potential is energy that is being stored due to a stretched or compressed material.

Multiple Choice

What type of energy conversion takes place in a toaster?

• Electrical to Chemical

• Electrical to Thermal

• Chemical to Radiant

• Thermal to Chemical

Multiple Choice

What type of energy conversion takes place in photosynthesis?

• Chemical to Radiant

• Electrical to Thermal

• Thermal to Kinetic

• Radiant to Chemical

This equation will help you keep track of Mechanical Energy during common conversions!

Notice as the pendulum swings, it will always have the same TE (TOTAL ENERGY).

• highpoint of the swing = high PE and low KE.

• lowpoint of the swing = high KE and low PE.

Notice that the Total Energy is always 50,000 J

Notice that the red KE column and Blue PE column always add up to the yellow Total Mechanical Energy Column!

Notice at the beginning there are a total of 40,000 J of energy.

Multiple Choice

How much KE is there at point B?

• 80,000 J

• 0 J

• 20,000 J

• 25,000 J

Multiple Choice

How much PE is there at point F?

• 40,000 J

• 0 J

• 20,000 J

• 5,000 J

Why doesn't the ping pong ball bounce back up to the original height?

Multiple Choice

What does the word dissipate mean?

• shock

• seem to vanish

• to let someone down

• to expect with excitement

Poll

If I can ignore energy dissipated due to things like heat, sound & friction, I can track the kinetic energy and potential energy in a given situation.

• Yes, definitely!

• Probably, but I'd like more examples.

• I don't even know what kinetic and potential energy are!