Which ball wins?

[gwiyomi17]

My answer for a is the Y-track

My reason (for b) is because Y-track has more steeper slope which will give the ball a greater speed.

 

 

I need to explain it further, I just need help with letter B.

I already finished C and D

oh i think i posted my question in the wrong section, sorry

[J.C.MacSwell]

My answer for a is the Y-track

My reason (for b) is because Y-track has more steeper slope which will give the ball a greater speed.

 

 

I need to explain it further, I just need help with letter B.

I already finished C and D

oh i think i posted my question in the wrong section, sorry

I assume this is homework. Can you tell us your answers for c) and d). I think that may help with answering b).

[CaptainPanic]

!

Moderator Note

 

oh i think i posted my question in the wrong section, sorry

 

No worries. That's what you have your friendly moderators for. We'll move a post on request (and I read this as a request). It's put in the homework section now.

[studiot]

Look here for brachistochrone.

 

http://www.google.co.uk/search?hl=en-GB&source=hp&q=brachistochrone&gbv=2&oq=brachistochrone&gs_l=heirloom-hp.1.0.0l10.1297.4797.0.10735.15.10.0.5.5.0.172.1469.0j10.10.0....0...1ac.1.34.heirloom-hp..0.15.1657._XFvibAUHQM

Edited April 2, 2014 by studiot

[rktpro]

Familiar with conservation of energy?

[gwiyomi17]

I assume this is homework. Can you tell us your answers for c) and d). I think that may help with answering b).

For c

I said that the total energy after the balls were realeased is the same or equal to their total energy before they were released since friction is neglected. (energy is conserved)

 

for d

i solved it using the conservation of energy

and i got v=sqrt(2gh)

 

 

!

Moderator Note

 

 

No worries. That's what you have your friendly moderators for. We'll move a post on request (and I read this as a request). It's put in the homework section now.

THank you very much

 

 

Look here for brachistochrone.

 

http://www.google.co.uk/search?hl=en-GB&source=hp&q=brachistochrone&gbv=2&oq=brachistochrone&gs_l=heirloom-hp.1.0.0l10.1297.4797.0.10735.15.10.0.5.5.0.172.1469.0j10.10.0....0...1ac.1.34.heirloom-hp..0.15.1657._XFvibAUHQM

I alrready searched for it, but the mathematical explanations are too advanced for my level so I don't quite understand it but the videos are interesting

 

 

Familiar with conservation of energy?

Yes

[J.C.MacSwell]

For c

I said that the total energy after the balls were realeased is the same or equal to their total energy before they were released since friction is neglected. (energy is conserved)

 

for d

i solved it using the conservation of energy

and i got v=sqrt(2gh)

 

 

OK, so you are assuming no losses due to friction and disregarding the rotational energy...an idealized case.

 

So you know they are both at the same speed at the bottom, and that Y has a slightly longer path, though it is not defined exactly it is a smooth curve.

 

Which one accelerates faster at the start?

 

What is the speed of X, halfway along its path?

 

How much faster is Y moving, halfway along it's path?