More Friction

We finished our science section on friction. K. knows that friction:

1. is caused when 2 things rub together
2. slows things down
• ramp experiments
3. heats things up
• rub hands together
• pull nail from block of wood
• sanding wood
4. wears things away
• sand rough piece of wood
5. can be decreased by using oil or other lubricant
• rub 2 pieces of sand paper together, then put vasoline on them and rub them together -- notice the difference
• rub 2 crackers together, then put peanut butter or butter on them and rub them together -- notice the difference -- then eat them
6. is useful
• write/draw on construction paper with chalk, then dip chalk in vasoline and try writing
• open a jar, then try opening the jar with soapy hands
• turn a door know, then try turning the door knob with soapy hands