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A section of a rollercoaster is shown below. If the 17,500 kg rollercoaster momentarily comes to rest at point A, where it is 19 m in the air, how fast is it going at point D?

User Regis Zaleman
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1 Answer

14 votes
14 votes

Answer:

Step-by-step explanation:

Impossible to say without knowing how high point D is.

If we ignore friction, the energy converted from potential energy will exist as kinetic energy.

let d be the height in meters of point D "in the air"

mg(19 - d) = ½mv²

m is common so divides out

g(19 - d) = ½v²

v = √(2g(19 - d))

no sense in making g any more precise than the height. g = 9.8

v = √(2(9.8)(19 - d))

v = √(19.6(19 - d))

User Pterrat
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