Assignment:
Problem 1
Two students decide to balance various objects against crayons from a box that has never been opened. They find that their class gerbil, Greta, will balance 40 crayons. These students also found that Greta Would balance 80 clothespins.
1. What is the mass of Greta? Express your answer in two different ways.
2. Use the information given above to determine (1) the number of crayons that will balance one clothespin, and (2) the number of clothespins that will balance one crayon. Explain your reasoning.
3. Would the students have been able to use the crayons if the crayons from the box have previously been used for coloring? Explain.
Problem 2
Two masses are hanging on a meter stick suspended at its center. On the right side, an object with a mass of 200 square nuts is 10 cm from the fulcrum, and on the left side, an object that balances 100 square nuts is 20 cm from the fulcrum.
1. Is the system balanced?
2. Now the mass of the 100 square nut object is decreased by an amount m. How much farther must the diminished object be moved from the fulcrum to maintain the balance?
Problem 3
You and your partner each find the mass of a piece of aluminum on your balance. You obtain 10.612 g, and your partner obtains 10.638 g.
Your partner says: "Well, one of us definitely did something incorrectly."
Do you agree or disagree? Explain your reasoning.