Thursday, August 19, 2010

How many pennies in a cup?


Purpose: I have students do this lab at the beginning of the year to help
illustrate the scientific process. The main goal is to show that it is
okay for a hypothesis to be incorrect.

Problem
: How many pennies can you put into a cup of water
before it overflows?

Hypothesis
:

Experiment: Supplies - Dixie
cups (3 oz), Water, 50-60 pennies per group

Step 1
- Fill the Dixie cup with water until it nearly overflows (a few
millimeters from the top)

Step 2 - Carefully drop pennies into the cup, 1 at a time, until the water
overflows outside the cup.

Independent Variable: Group

Dependent Variable: # of pennies in cup





Results:
Group #Number of Pennies









Conclusion:

Possible Errors/Things to look out for:
1. Be careful not to drop pennies in and cause a splash, let pennies into water gently.
2. Make sure to fill to top of cup or just measure out 3 oz.
3. Use tally marks to keep track of pennies.
4. Have students alternate for who drops the penny.