Solve Motion Question for Frictionless Rollercoaster

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The discussion revolves around a physics problem involving a frictionless rollercoaster with a height of 99m and a vertical drop of 49m. Key calculations include determining the acceleration, time to complete the drop, final speed, and kinetic energy using the conservation of energy principle. Participants confirm that the car experiences free fall, resulting in a sensation of 1G rather than weightlessness. The calculations provided by one participant indicate that they align with expected outcomes. The thread emphasizes the straightforward nature of the problem and the application of fundamental physics concepts.
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Nice, easy fun really.

Homework Statement



There is a frictionless rollercoaster, at a height of 99m. The mass of the car is 2000kg, weight is 19 613N. The initial velocity of the car suspended at the top is 0, it is then dropped down a sheer (90 degrees) vertical drop for 49m.

GPE is ~1 960 000J

I need to calculate the acceleration of the car after it has dropped, and the time it takes to complete the 49m drop, as well as the final speed it is travelling. Kinetic energy couldn't hurt either :p

attachment.php?attachmentid=24679&stc=1&d=1269664269.png


Homework Equations


5 equations of motion.


The Attempt at a Solution


Meh, I've just rearranged a formula to find acceleration, but i don't have time or final velocity to work off.

Cheers guys, no clue where to start.
 

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Use law of conservation of energy.
Since roller coaster is frictionless, car is falling freely.
 
Cheers mate, I've done the calculations all seems to work out fine.

However, under freefall, you just feel 1G right, not weightlessness?
 
blueparukia said:
Cheers mate, I've done the calculations all seems to work out fine.

However, under freefall, you just feel 1G right, not weightlessness?
Yes. 1 g.
 
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