Vertical Circle Question - Please Help (1 Viewer)

[OreoMcFlurry]

Hey Everyone, I was just doing a question from a physics paper based on vertical circles and I just don't understand this at all:


I'd be awesome if someone could show the working required to get the answer because I'm seriously lost whenever it comes to vertical circles rip.
Thank you very much.

 

[Lith_30]

We know that the passengers have to feel weightlessness at the top of the loop, therefore the centripetal force must be equal to the gravitational force.


Then we need to use conservation of energy to find a relationship between the height and the velocity



Since we know that the cart will be at the top of the loop, we can take the final height to be 16, and we can sub in the velocity that we got in the previous steps.



By subtracting 16 from 20 we get 4, which means A is the answer.

 

[OreoMcFlurry]

We know that the passengers have to feel weightlessness at the top of the loop, therefore the centripetal force must be equal to the gravitational force.


Then we need to use conservation of energy to find a relationship between the height and the velocity



Since we know that the cart will be at the top of the loop, we can take the final height to be 16, and we can sub in the velocity that we got in the previous steps.



By subtracting 16 from 20 we get 4, which means A is the answer.

Damn, thank you very much! It makes a lot of sense now that you've explained it

 

[notme123]

We know that the passengers have to feel weightlessness at the top of the loop, therefore the centripetal force must be equal to the gravitational force.


Then we need to use conservation of energy to find a relationship between the height and the velocity



Since we know that the cart will be at the top of the loop, we can take the final height to be 16, and we can sub in the velocity that we got in the previous steps.



By subtracting 16 from 20 we get 4, which means A is the answer.

to simplify you can make the top of the loop the ground so that you only need to do mgd=1/2 mv^2 when doing LCE and you get d=4 if v=8.85...