Recent content by kellyneedshelp

ok, well i tried using A=pi*(.0252m)^2 = .001995 m^2 and P = 1.239atm to get F = (1.239)*(.001995) = .0007868 N and then use F=-kx where x=0.0341m to get k=.07249 N/m but this is not the right answer. am i not following what you are saying correctly? thanks=)

do you mean use the area of one end of the cylinder, like just pi*r^2?

isn't the area of a cylinder = 2*pi*r*h ? how do i find the area of the cylinder without knowing its height/length? thanks!

hi, i am having trouble with this problem: A cylinder with a diameter of 5.04 cm has a movable piston attached to a horizontal spring. The cylinder contains 1.40 liters of an ideal gas at 20.9°C and 0.99 atm pressure. Under these conditions, the spring is unstretched. The temperature of the...

I do not understand what is meant in this question: An open organ pipe has a fundamental frequency of 430 Hz. A closed organ pipe has a fundamental frequency that is the second harmonic of the open organ pipe. What are the lengths of the two pipes? Does the bolded part mean that the...

Do accused students have the opportunity to defend themselves in an Honor Court that decides the student's fate (that is how my university handles these things), or does the instructor play both judge and juror?

aha! so it is just off by one decimal place:cool: thanks everyone, i get it!

ohhh i did not know that, thanks! so does this look right, then: tan(47.8)=x/55566m, so x=61.27km? it still says this is wrong, so am i setting it up wrong still? thanks!

should i not divide by two? it is difficult to explain why i thought i should in writing but i'll try: so the cone is horizontal to the ground (on its side, for a lack of a better way of explaining it), with the imaginary parallel horizon going through the cone, splitting it in half, sort of...

anyone know if i am picturing the triangle correctly? thanks!

so the angle of the cone is found by: sin(theta)=1/Mach#=.7407, so theta = 47.8degrees (approx). since the plane is flying horizontal, divide this angle by 2 and get 23.9degrees (1) (3)triangle is a right triangel with sides as distances from "you" to point overhead and point overhead to point...

so any ideas on how to factor in the speed of the aircraft with the speed at which the sound reaches the observer?

ok thank you, although apparently 4.116 km is not right either so i am still confused about this one...

do you mean that i should just use the velocity of the speed of sound? so, 343 m/s * 12.0 s = 4116 m = 4.116 km ? i was thinking the velocity of the plane does matter b/c since it is above mach 1, it makes a cone shaped wave, but does this not matter? thank you!

sorry, I am not familiar with how to use that kind of equation, could you explain what it means, please? thanks!