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Centripetal acceleration of Earth around Sun?

  • Thread starter psycovic23
  • Start date
New question: centripetal force?

I can't seem to get the right answer...

R = 1.50 x 10^11

and I figure that 1 day/rev = 86400 sec/rev

So: [tex]\frac {2 \pi 1.50 * 10^{11}}{86400}[/tex] is the velocity, and then plug that into [tex]\frac {v^2}{r}[/tex] but I keep on getting 700 something..what am I doing wrong?



Question 2: At what minimum speed must a roller coaster be traveling when upside down at the top of a circle if the passengers are not to fall out? R = 8.6m

What I think you have to do is
[tex] mg + F_c = m * \frac {v^2}{R}[/tex]

but I don't know what F would be...or am I approaching this the wrong way?
 
Last edited:

dextercioby

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psycovic23 said:
I can't seem to get the right answer...
R = 1.50 x 10^11
and I figure that 1 day/rev = 86400 sec/rev
So: [tex]\frac {2 \pi 1.50 * 10^{11}}{86400}[/tex] is the velocity, and then plug that into [tex]\frac {v^2}{r}[/tex] but I keep on getting 700 something..what am I doing wrong?
Whoever told you that the Earth circles (on an ellipse :tongue2: ) the Sun in one day (86400s) is a WACKO!!!!!!!!!!!!! :surprised :surprised

Daniel.

PS.I hope u see the error. :tongue2:
 
Wow. I'm dumb :tongue2:
 
*Bump for new question*
 
F

futb0l

Hmm - Newton's second law(the mass cancels)... so, the centripetal acceleration has to be bigger than the gravitational acceleration.

[tex]
\frac{v^2}{r} > -g
[/tex]
 

Doc Al

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psycovic23 said:
Question 2: At what minimum speed must a roller coaster be traveling when upside down at the top of a circle if the passengers are not to fall out? R = 8.6m

What I think you have to do is
[tex] mg + F_c = m * \frac {v^2}{R}[/tex]

but I don't know what F would be...or am I approaching this the wrong way?
So far, so good. What you call [itex]F_c[/itex] is the force exerted by the coaster on the passenger. The minimum speed of the coaster is that which will make [itex]F_c = 0[/itex]. When that force goes to zero, it means that the passengers are beginning to lose contact with the seat.
 
Ah, thank you very much!
 

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