Type of Ride:Roller Coaster, Gravity driven
- To determine the height of a distant object.
- To apply estimation skills in determining distances.
- To accurately use a stop watch.
- To calculate the speed of the coaster train at various points during the ride.
- To relate qualitative observations of forces during the ride.
Key Terms:Acceleration, Friction, Force, Inertia, Kinetic Energy, Mass, Momentum, Potential Energy, Velocity.
Useful Formulas:For similar triangles: h1 / h2 = l1 / l2
For triangulation: h1 = L tan q
Total height = h1 + h2
For Speed: S = d / t
Conversions:88 ft/s = 60 mph; 1 ft/s Å 1 mph; 1 m/s Å 2mph
1 ft/s = 0.30 m/s; 1 mph = 1.60 km/hr
Data:Length of track = 2,300 ft. or 700 m
Height of first hill = 100 ft or 30.3 m
Materials:meter/yard sticks, protractors, thread, small fishing weights, data books, and chalk.
1. Using Similar Triangles:* Review proportions with students
* Have students record each others heights .
* Students should then find the average of one walking pace. (walk along a meter/yard stick )
* Record both personal height & pace in lab book.
* Measuring shadows on a sunny day. (Partners should record each others shadow , then measure or pace off the shadow of a distant object cast on the playground, ie: flagpole, building, or telephone pole.)
* Bring data back into the class room to do calculations.
*Compare answers, if possible obtain exact height of pole to compare with students measures.
2.Using Triangulation:* Prepare protractor for measuring < s by stringing a fishing line through the vertex hole in protractor bring line together using a pinch fishing weight.
* The straight edge of the protractor will be used as a sight line; the angle measure is read by the partner eyeing the plumb line.(see worksheet).
* Review with students how to determine the tangent of an angle.
* Student partners should record each others height from the eye level to ground (h1)
* Return to the outdoors. Students should take a position a measurable distance from the flagpole, telephone pole etc..
* Protractors should be used to measure angle to top of pole from a standing position facing the pole. The angle measure is recorded by the partner.
* Pace off or measure the distance from the flagpole.
* Fit data into formula and solve for h .
Materials:Stopwatch, skateboard/coaster or similar, and lab book.
3. Measuring Speed* Measure out the distance of your chosen ramp or hill, a trundle wheel is helpful in measuring the course.
* Student at top of ramp roll down ramp / hill at signal of timer.
* Timers record duration of ride.
* Repeated trials are necessary to improve accuracy and to give everyone a chance to race down the ramp / hill.
* A variation to be practiced is timing as the racers pass by a single point.
* Make a "train" of racers ( two students back-to-back on skateboards).
* Measure the total length of the "train".