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Speeding Bus |
In a famous movie, Speed, a speeding bus jumps an unfinished bridge. Is this possible?
Construct a model with the following specifications-make sure view | numbers and units are set correctly
- 10 000 lb Bus (rectangle) (window | properties); 50 feet long and 10 ft high (window | geometry)
- 2 foot radius wheels (window | geometry), 10 feet in from the ends of the bus; 200 lbs for each pair of tires
- Vx varied by a control (ft/s); (Select the bus - Define | new control | initial x velocity)
- 100 foot wide gap to jump.
- World | Accuracy = accurate
- Using window | appearance give each part a name - e.g. select the rectangle and type bus body
You can also change colors and other features
1a. Determine the minimum speed necessary in ft/s (2 sig. fig. ) and mph for the bus to jump the chasm (which is level).
1b. Does changing the accuracy of the calculations change your results? Try this:
Reset World | Accuracy | Animation step - 200 steps/second, and redo part (a).
Leave the Accuracy at this setting for the following:
2a. For a bus traveling at Vx = 80 mph (118 ft/s), construct two100 ft ramps on both sides of the gap and determine the range of angles (equal on both sides) with the horizontal they could be for the bus to jump the bridge.
It is helpful to use an actuator to move the ramp up and down. It should be of type length (window | properties)
(If you would like to use a control to change the length - Select the actuator - Define | new control | length)
2b. What angle is the safest to keep from horribly maiming the passengers? (Select the ramp - measure | position | rotation graph)
