Friction and Heat: Energy's Hidden Transfer

Do you prefer salty or sweet foods?

• salty

• sweet

What is friction?

• A figment of your imagingation.

• An imaginary creature.

• A part of a whole.

• The resistance between two surfaces.

When objects move against each other, some kinetic motion energy is transferred into

• heat

• friction

• acorn dollars

• french fries

Which surfaces produce more friction?

• 
• 

Do cars and airplanes have the same kinds of tires? Why, or why not?

How does friction help us in our daily lives?

• It doesn't help.

• It makes things move faster.

• It helps control motion.