Off to the Races s1

Name: ______

Soaring Straws Lab-

Purpose: To determine how the PE of a straw rocket depends on the elastic PE of the rubber band launcher Hypothesis: ______

Materials: scissors meter stick rubber band masking tape straws empty toilet tissue tube marker

Procedure: Part 1: 1. Cut a rubber band and gently stretch it across the open end of the tube. Tape it to make the launcher. 2. Cut 3 cm off 1 straw. Lay 2 uncut straws side by side on the table with the 3-cm piece of straw between them. Make sure they are even. Tape the straws together side by side. 3. Starting from the un-taped end, make marks every centimeter on one of the long straws. *(This is the rocket.) 4. Tape a meter stick to the wall to measure the height is rises. 5. Load the launcher (near the meter stick) by placing the rocket over the rubber band and pulling down through the tube. 6. Note the amount of stretch and release it straight up. Record data. 7. Repeat for 3 trials & calculate the average & record in your chart. 8. Use five different amounts of stretch and repeat step 8. 9. Find GPE for each amount of stretch using the average height with this formula: PE= mgh Where g= gravitational acceleration 9.8 m/s2 10. Find the mass of rocket: ______g (Since you have measured the mass in grams, the unit of energy is the millijoule (mJ), which is one thousandth of a joule. Record the results in your data table). 11. Remember to convert cm to meters (10 cm = 0.1 m)

Amount of Height Height Height Average GPE stretch (cm) (Trial 1) (m) (Trial 2) (m) (Trial 3)(m) Height (m) (mJ) Explain:

1. Which variable in your data table is the manipulated variable? The responding variable? How do you know? ______

2. Graph your results. Show gravitational potential energy on the vertical axis and amount of stretch on the horizontal axis.

1. How does this experiment demonstrate potential and kinetic energy? ______

2. How did the stretch of the rubber band affect the distance it traveled?

______

3. How does the amount of stretch in the rubber band affect the amount of PE and KE? ______