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CORKSCREW. QUESTION: The roller coaster is at the top of the hill 20m high and moving at a speed of 10m/sec. a ) (assume no friction) How fast will the coaster be moving at the bottom of the hill before going into the loop?.
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QUESTION: The roller coaster is at the top of the hill 20m high and moving at a speed of 10m/sec.
a) (assume no friction) How fast will the coaster be moving at the bottom of the hill before going into the loop?
b) (assume no friction) How fast will the roller coaster be moving at the top of a loop which is 15m high?
The density of air is 1.75 kg/m3, the area of the coaster is 4m2, and the drag coefficient for the coaster is 0.8.
c) (in a perfect physics world) If the wind starts up after going out of the loop; a drag force is created to stop the coaster. Find the deceleration of the coaster if the coaster is running on a flat track.
A Since gravitational potential energy is 0 at the bottom; PE and mass cancels out. ½v2 = ½v2 250 = ½v2 2 x 250 = v2 √500 = v 22.36 = v
B PE + KE = PE + KE Mgh + 1/2mv2 = mgh + 1/2mv2 (9.8)(20) + ½(10)2 = (9.8)(15) + ½ v2 196 + 50 = 147 + ½ v2 2(246-147) = v2 √198 = v 14.07 = v
CFd = ma½pv2CdA = ma ½(1.75)(22.36)2(0.8)(4) = 400a1399.91488 = 400a1399.91488/400 = a3.50 m/s2 = a