Barbie Launcher Can you help barbie and her pool toys get into the hot tub?

Your Goal: 1. Create a zip line using fishing line and use gravity and projectile motion to get a barbie into a hot tub near the bottom of the slide. 2. Create a catupult to launch Barbie’s toys into the hot tub.

The Basics You will work in groups of 2 or 3 students. You will have 3 full class days to build, test and analyze Your group may choose what they want to build You may not use anything that would be considered inappropriate at school KITS are not allowed

Zip Line The line should have a comfortable carriage for Barbie and a release mechanism that operates on its own once she is released at the top of the line. Barbie will accelerate down the line, converting her vertical velocity into horizontal velocity as she leaves the line at a fixed position determined by YOU. She should land IN the hot tub. She MUST have a horizontal component of motion when she leaves the line. The purpose of this activity is to investigate an example of projectile motion.

You will get 3 official trials and Barbie must land consistently in the tub. Barbie should not be damaged, held in an uncomfortable position, or be naked at any time. Any inappropriate comments, positions, etc. will cause you to lose points. The tub is centered, 1.00 m from the tied off far position of the zip line. 60 % of the Barbie must be in the hot tub in order to get full credit for the event. A Barbie that bounces out counts as an “ In ” if most of her was in when she bounced out. Barbie dolls have a relatively high coefficient of restitution ( bounce ).

Your challenge is to build a miniature catapult to chunk a Barbie toy into the hot tub. Each student will be provided with a toy for practice. You must use school appropriate materials to make your catapult. ( no alcoholic beverages, explosives, or obscene language. ) Your catapult may not be powered by electricity, batteries, etc. KITS are NOT ALLOWED. Catapult

Choose your groups wisely You will have three full class days to do the following: a ) build and test a prototype b ) collect data c ) demonstrate your success to your instructor and d ) complete the calculations.

Timeline Step 1: Choose your groups and sketch a design. Make a list of what you need to bring to class. This list will be turned in. DATE: Oct. 29 Step 2: Bring materials to class – you will receive a grade based on whether you brought materials. DATE: Oct. 20-Nov. 1 Step 3: Build and test your design in class. DATE: Oct. 30-Nov. 1 Step 4: Demonstrate your design and data analysis. DATE: Nov. 2

What you will turn in Rubric Point Value Sketch of design10 points Materials needed – contributed to the group 10 points Diagram of launch area with all variables labeled. 10 points Data analysis and calculations.40 points Correctly launch all 3 attempts30 points Correctly launch 2 attempts20 points Correctly launch 1 attempt10 points Fail to hit target but have a working mechanism 5 points Mechanism does not work0 points

The Physics - Launcher Release

The Physics behind the Launcher You will determine the horizontal distance your barbie will travel and have me place the hot tub at that distance. You will then use your data to solve for all of the projectile variables we have discussed in class. Make sure your results are repeatable.

The Physics behind the launcher This is a projectile motion problem once the Barbie leaves the line. You are not allowed to have an abrupt stop and the Barbie drop into the hot tub. She must have some horizontal component of motion when she leaves the line. You will need to time her down the line, measure the height of her fall to determine the time she is in the air, measure the height she falls as she goes down the line and measure the angle of your zip line.

The Physics: Catapult You will need to determine the best angle to hit a required distance.

Helpful websites: So many different catapults here: how-to-build-a-catapult.htm Just search catapult at instructables: pult/