Barbie™ Bungee Jumping Name : __________________________________ Date : _________ Period : ___ Barbie™ Bungee Jumping Graphing and Extrapolating Data while investigating forces Team members have been hired to work for the Evil Knievel Entertainment Company. This company provides rock climbing, sky diving, “extreme skateboarding”, and hang gliding adventures to the public. The current market research indicates that the company should add bungee jumping to its list of entertainment services. As part of the preliminary research, the management has assigned teams the task of working out the details of the jump to ensure a safe, yet thrilling experience. The company has several sites planned for bungee jumping and each site is at a different height. PURPOSE To ensure a safe and thrilling jump, you will determine the relationship between the jump height and the number of rubber bands used to make the bungee cord. You must allow your action figure to come as close to the floor as possible without sustaining any injuries or fatalities. MATERIALS meter stick rubber bands (7 to start) balance 1 Barbie doll PROCEDURE 1. Use one rubber band to secure Barbie’s™ ankles together and to serve as a point of attachment for the bungee cord. 2. Mass Barbie™ on the balance. Record the mass in Data Table 1 in both grams and kilograms. 3. Construct a bungee cord composed of 2 rubber bands and attach it to Barbie’s™ ankles. Barbie will fall from a standing position, plunging head first throughout this activity. Measure the initial length ( in meters!) of the 2-band bungee cord you constructed once it is attached to Barbie’s™ ankles. 4. For the first few measurements, place the meter stick upright and hold Barbie™ as if she is standing on top of it. This will be her initial launch platform. Test drop Barbie™ several times to practice taking readings. Repeat this jump two more times and record the data (again in meters!!). 5. Add a rubber band to your attached bungee cord. Measure the new cord length. Drop Barbie™ three times and record the data. 6. Repeat step 5 until you have a total of 6 rubber bands in your bungee cord. Record the data each time. 7. Average your data and then graph each point on the graph labeled “Number of rubber bands vs drop distance” 8. Draw a “best fit” line on your graph. Remember that a best fit line will not necessarily go through all of the points. You are not connecting the dots!! However, you will have a line that gets as close as possible to the majority of the points. It should have equal numbers of points above the line as below the line. 9. Use this line to extrapolate (predict based on information) how many rubber bands will be required to drop Barbie™ safely from the distance your instructor gives you. Distance = ____________________ Results = lived / died / maimed # of rubber bands needed _________ Barbie™ Bungee Jumping Name : __________________________________ Date : _________ Period : ___ Barbie™ Bungee Jumping Graphing and Extrapolating Data while investigating forces DATA AND OBSERVATIONS________________________________________________ Data Table Mass of Barbie™ = ____________ g Number of Rubber bands = _______________ kg Initial Length of Bungee (m) Maximum Drop Distance Trial 1 Trial 2 Trial 3 Average Barbie™ Bungee Jumping Name : __________________________________ Date : _________ Period : ___ Number of Rubber Bands vs Drop Distance Conclusion questions__________________________________________________ 1. The slope of a line can be calculated by taking two points on the line and using the equation Y2 - Y1 slope = -----------------X2 - X1 Find the slope of your line. Barbie’s™ height is approximately 0.10 m. This means that the equation of your line is y = mx + b where y= your drop distance in meters, m= your slope, x= the number of rubber bands, and b winds up being Barbie’s height of 0.10 m. Write the equation for your line in the space below. y = ___ x + 0.30 Barbie™ Bungee Jumping Name : __________________________________ Date : _________ Period : ___ 2. Using the equation of your best fit line from question #1, calculate how many rubber bands would be required to allow Barbie™ a successful, yet thrilling jump from a height of 30 m (~100 ft). (Hint: put the 30 in place of the y and solve for x.) 3. Calculate the stretch coefficient for the trial using 4 rubber bands by using the following formula: Stretch factor = Stretch factor = amount of stretch (Average drop distance – initial length of bungee) -----------------------------------------------------------------------mass of Barbie™ 4. List all of the forces that affected Barbie™ from beginning to end of her jump. 5. Calculate Barbie’s™ weight using the formula Wt = m · g [weight = mass · acceleration due to gravity (9.8 m/s2) ] Remember to convert Barbie’s™ mass from grams to kilograms (mass in grams ⁄ 1000) Barbie’s™ weight = _____________ N 6. Ken wants to jump and have some fun too. Barbie™ offers to loan Ken her bungee cord, but warns him that it may not be a safe idea. Why would it be a bad idea for Ken to use Barbie’s™ bungee cord? (Think differences)