Show Number 901

LUGE

• Would you like to take a ride on the luge?
• Why would athletes want to analyze their movements?
• How important is the start of the race?
• What kind and amount of strength does running a luge require?

The Olympic luge event was introduced in 1964 at Innsbruck-Igis, Austria. The word luge is French for "racing sled." Lugers careen down the course feet first while lying on their backs. The luge sled was originally controlled by a hand-held strap which guided the front of the runner. Now luges are steered by the lugers exerting pressure on the sides of the car with their feet and shoulders.

Sliders have limited visibility because of their body position combined with speeds of up to 80 miles per hour. Hairpin turns in the course and rules requiring one of the four runs to be run at night make this event one of the most dangerous in the Olympics. It is so dangerous, in fact, that in 1964 a Polish-born British slider named Kazimierz Kay-Skrzypeski was killed in a luge accident, and later, two other German lugers were severely injured.

Several physical forces are demonstrated by a luge event. One is friction, the force that slows down moving objects when two surfaces rub together. Of course, the ice on the luge course minimizes the potential for friction on the surface. Lugers attempt to further reduce the force of friction by using the most slippery materials possible to construct the luge itself. The weight of the luger places pressure on the ice, melting it and creating a slippery layer of water that further reduces friction. But there are rules about overcoming friction. In 1968, the German Women's Olympic Team was disqualified for heating the runners on their sleds!

Another physical force involved with luge is gravity. Gravity causes acceleration and helps the luge move. The forward motion is balanced by the friction of air pushing against the luge. Because of this air friction, designers must use aerodynamic principles to reduce the wind drag to a bare minimum. Often they use tight rubberized suits, special helmets with rounded face shields or smooth sleds designed with a low center of gravity.

Things to Talk About

1. Oftentimes, lugers are filmed on high speed video that is then converted to computer graphics to analyze performance. The use of this technology is a trend in modern sports and in the Olympics. By knowing more about physics and how it affects their performance, athletes can modify their training and practice sessions to improve their performance. What would you expect computer analysis to tell you about your favorite sport?

Friction--The force that acts to resist the relative motion (or attempted motion) of objects or materials that are in contact.

Air Resistance--The force that acts on something moving through the air.

Weight--The force on a body of matter due to the gravitational attraction of another body (commonly the Earth).

Velocity--Speed together with the direction of motion.

Acceleration--The rate at which velocity is changing. The change may be in magnitude, direction or both.

Resources

• Freier, G.D. and Anderson, F.J. A Demonstration Handbook for Physics Teaching. College Park, MD: American Association of Physics Teachers, 1983.
• Henry, Sara J. "The Need for Speed." Women's Sport and Fitness, Jan./Feb. 1991, pp. 58-59.
• Milgrom, Harry. First Experiments with Gravity. E. P. Dutton & Co., New York: 1966.
• Sklarwitz, Norman. "80 M. P. H. on Ice", Boys Life, Dec. 1990, pp. 36-37.
• Wallechinsky, David. The Complete Book of the Olympics. Crawfordsville, Indiana: R. R. Donneley & Sons Co., 1985.

Additional Sources of Information

• U. S. Luge Association Box 651 Lake Placid, NY 12946 (518) 523-2071

Activity Page

CONSTRUCT A LUGE

You can design your own luge and luge course. Try and find ways to make your luge car travel faster and then start racing!

Main Activity

By applying the physical forces of friction, the force that slows objects down when they rub together, and gravity, which helps the luge accelerate, you can design super fast luges and exciting luge courses.

Materials:

• Graph paper
• Card board
• Rubber bands
• Waxed paper
• Butcher paper
• Aluminum foil
• Several toy cars of different shapes and sizes (Or, try to make your own luge with popsicle sticks, tongue depressers and glue)
• Stop watch

1. Have the class discuss what kind of course to build for your cars or luge. Choose what kinds of variables you want in your course, like the number of curves, angle of turns, elevation or length of the course. You may want to add a drop hole so the car or luge could drop through to another chute below.

2. Once your class has chosen a plan, divide into two teams. One team will design and build the course, the other will select the best cars or build a miniature luge.

3. Once the chute is constructed and the cars are ready, begin timing how long it takes the cars or luges to complete the course. Run several time trials and record your observations. Graph the results.

4. Try to modify the cars or luges to make them go faster. Record and graph the times of these modified trials.

5. Discuss your modifications, observations, and graphs. Select one car or luge for the course and invite other classes to enter a luge contest.

Questions

1. What effect does a sharp curve have on the speed of your vehicle?

2. Should a luge course be designed so that the car's speed increases continuously? Should there be parts of the course that level the luge out? Why or why not?

3. What factors increase or diminish speed?

4. Find out what drag means. Is there drag in water? What effect might it have on aquatic animals?

5. What affects your speed when you are sledding? How could you find ways to go faster? Could you find better ways to control the turns?

Split up into several groups and discuss how friction helps us and how it hinders us in the things we do. See if you can find pictures that illustrate the effects friction has on our daily lives.

You can demonstrate the effects of air resistance when it interacts with gravity. Construct a paper parachute and attach it to a large iron washer. Hold another iron washer in your other hand. Drop the parachute with the washer and the solitary washer at the same time. Which washer reaches the floor last? Why?

Videotape a friend playing a sport or performing an activity. Using freeze frame or slow motion, analyze the performance in terms of physical forces like gravity, friction and drag. Help your friend improve his/her performance.

Sports like tobogganing and bobsledding are similar to the luge. Split the class into teams and have them investigate the similarities and the differences between each sport. Pay particular attention to how each sport allows for physical forces like gravity, friction and air resistance. Go sledding if there is snow in your area. Each team should prepare a report to present to the class.

WE ENCOURAGE DUPLICATION FOR EDUCATIONAL USE!

Educational materials developed with the National Science Teachers Association.