Minimum speed at the circular track

AI Thread Summary
The discussion centers on determining the minimum speed a car must have at the top of a circular track loop. Three methods for calculating this speed are presented, with one participant favoring the third method under the condition that the height (H) is greater than twice the radius (2r). There is a query regarding the consideration of forces at the top of the loop, emphasizing the importance of centripetal force in maintaining motion. The conclusion suggests that if the height condition is met, the chosen method will yield sufficient speed for safe navigation of the loop. The focus remains on ensuring that the car maintains the necessary centripetal force at the loop's apex.
inky
Messages
99
Reaction score
1

Homework Statement



What is the minimum speed of the car must have at the top of the loop? There are three methods. I would like to know which method or answer is correct.

Please see attached file.

Homework Equations



Please see attached file.


The Attempt at a Solution



Please see attached file.
 

Attachments

Physics news on Phys.org
I would choose the third one,provided that H> 2r.
 
rock.freak667 said:
I would choose the third one,provided that H> 2r.

Thanks a lot. Why didn't consider the force at the top?
 
I think if H> 2r, then the speed will be enough to provide the centripetal force.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top