Recent content by pdonovan

Homework Statement Interstellar space, far from any stars, is filled with a very low density of hydrogen atoms (H, not ). The number density is about and the temperature is about 3 K. What is the edge length L of an LxLxL cube of gas with 1.0 J of thermal energy? I found: P =...

Then which values are wrong in the Vrms = sqrt(3KbT / m) formula? I have T = 3 and if m = 1, then Vrms = 1.11 x 10 ^ -11 which is wrong. And if m =1660x10^-27g it is too big (around 8.6).

Now I have... 4.14x10-17pa = (1/3)(1/10-6)mVrms2 1.242x10-22 = mVrms2 74819.28 = Vrms2 Vrms = 275.64m/s So something is definitely wrong, because the atom should be moving very slowly.

Thank you very much, that was the correct answer. Now, how would I got about finding Vrms? I know p = (1/3)(N/V)mVrms2 So, p = 4.14x10-17 N = 1 V = 10-6 m = 1u = 1.66x10-27 And found Vrms = .86m/s, but this is incorrect. I think my m or v might be incorrect.

Homework Statement Interstellar space, far from any stars, is filled with a very low density of hydrogen atoms (H, not H2). The number density is about 1atom / cm3 and the temperature is about 3 K. Estimate the pressure in interstellar space. Give your answer in Pa and in atm. Homework...

Thank you for the tip, but I still haven't figured it out : / I have a<=b+c --> a/[(1+a)(1+b)(1+c)] <= (b+c)/[(1+a)(1+b)(1+c)] --> a/[(1+a)(1+b)(1+c)] <= b/[(1+a)(1+b)(1+c)] + c/[(1+a)(1+b)(1+c)]

Also, this is for all a,b,c >= 0.

Homework Statement Show: if a <= b + c, then a/(a + 1) <= (b / (b + 1)) + (c / (c + 1)) I'm really not sure where to start from the initial statement a <= b + c. I'm using this in order to show that the metric space e(a,b) = d(a,b)/(1+d(a,b)) exists. Any help would be greatly...

I'm trying to verify that if (M,d) is a metric space, then (N,e) is a metric space where e(a,b) = d(a,b) / (1 + d(a,b)). Everything was easy to verify except the triangle inequality. All I need is to show that: a <= b + c implies a / (1 + a) <= (b / (1 + b)) + (c / (1 + c) Any help...

The initial speed of the bullet.

Sorry for the lack of units, the question was copy pasted. A 2.3kg wood block hangs from the bottom of a 1.0kg, 1.2m long rod. The block and rod form a pendulum that swings on a frictionless pivot at the top end of the rod. A 10g bullet is fired into the block, where it sticks, causing the...

If anyone sees any minor errors in my calculations (or major!) please please help, I'm trying to figure this out before a test. Thank you.

1. A 2.3kg wood block hangs from the bottom of a 1.0kg, 1.2m long rod. The block and rod form a pendulum that swings on a frictionless pivot at the top end of the rod. A 10g bullet is fired into the block, where it sticks, causing the pendulum to swing out to a 33degree angle.Homework Equations...

Question: You and your friend Peter are putting new shingles on a roof pitched at 25 . You're sitting on the very top of the roof when Peter, who is at the edge of the roof directly below you, 5.5 away, asks you for the box of nails. Rather than carry the 2.0 box of nails down to Peter, you...

How can Fnet = ma + Fweight when Fnet = ma?