Recent content by Gyro

Thank you for clearing that up, Borek.

I see. So using Kelvin is necessary then, because if I use Celsius or Fahrenheit, I would get an incorrect answer. I think that's what you mean by using standard units. Celsius and Fahrenheit are not for Gas Law questions. Is that what you mean? I'm not that good at chemistry and thermo...

huh? In your first sentence you say I did it wrong by using Pa and not atmospheres. Then in the next sentence you say it's ok though because I divided by Pa and that it seems right. I'm confused. Is the final temp correct? Thanks for your reply.

Homework Statement 250L of air initially at a pressure of 250Pa and a temperature of 50 degrees F is heated until the gas is at a pressure of 500 Pa and occupies 500L What is the final temperature of the air* in Kelvin. *Assume air behaves like an ideal gas. Homework Equations \frac...

Thanks for your help.

I think I get it now, maybe. Since theta = pi/3, you check multiples of that in the equation, not multiples of 2pi like I thought. So I plug in npi/3 for n = 1, 2, 3, 4, 5, ... and find all the values of n that make the equation 0 in the interval specified. Then I have my roots as 5pi/3, 7pi/3...

But how do I find the values that count? Wolphram also says \theta = \frac {1}{3}(6n\pi \pm \pi) but I don't know how to get that without looking at the plot. How do I get this generalized term from the data given? Thanks for your time.

Attached is the Wolfram plot

Hmmmm, I think I'm missing some roots in the interval because I have a composite of a cos theta and a cos 2theta. So should my answer be \theta = \frac {2n\pi + \pi}{3}\ for\ n = 3, 4, 5, 6, 7, \ and\ 8 Somebody please help. I'm having trouble seeing how the frequency of this equation can...

Wait, are you saying that because theta = pi/3, and the period is 2pi, then the following roots in the specified interval are 7pi/3 and 13pi/3? Which means \theta = \frac {2n\pi + \pi} {3} for\ n = 3 ,\ 6? I'm not the best at formalizing my math. Is this correct?

I guess what's troubling me is the power reduction formula gave me a sum of two cos functions and I wasn't sure what their combined frequency is, or period. If there is a term of cos2theta, shouldn't the period be 1/2, since the frequency is doubled? And if not, and the period is always 2pi...

Homework Statement Solve the equation 2cos^2\theta + 5cos\theta - 3 = 0\ for\ \frac{3\pi}{2}<\theta<5\pi Homework Equations quadratic equation, power reduction formula: cos^2\theta = \frac {1+cos2\theta}{2} The Attempt at a Solution First I tried using the quadratic...

Yes, but breaking it down helps to visualize it, no? And you asked for a way to express time, so I showed you. Plus, it asks for max altitude, this 'd' is only from free fall. We have to add the 'd' from rocket thrust upwards. Hope I helped.

Remeber that after engines fails, the only acceleration on the rocket is gravity.

When the engine fails, it's velocity is 190 m/s at 53 degrees from horizontal. Then in the vertical direction, you can use the equation Vf = Vi + at, where Vf = 0, Vi = 190sin53 m/s , a = -9.8 m/s^2, and isolate t. Go from there.