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1. Calculating Flux over the closed surface of a cylinder

For the mantel, the normal would be \hat{n} = \frac{<x,y,0>}{a} and for the disks, it would be \hat{n} = \frac{<0,0,z>}{b} From those two normal, I can take the dot product of normal with the vector and get the total flux? Sorry if I'm being slow...
2. Calculating Flux over the closed surface of a cylinder

Oh! I see what you mean. Would I have to add two more flux bounded by a circle to the total flux?
3. Calculating Flux over the closed surface of a cylinder

Wow haha, this would've save me more time My apologies, it should be \overrightarrow{r} = <acos\theta,bcos\theta , z> This is from the parametric description of a cylinder. End caps? My calculus is a bit rusty, its been about 2 years since I've worked on vector calculus.
4. Calculating Flux over the closed surface of a cylinder

I wanted to check my answer because I'm getting two different answers with the use of the the Divergence theorem. For the left part of the equation, I converted it so that I can evaluate the integral in polar coordinates. \oint \oint (\overrightarrow{V}\cdot\hat{n}) dS = \oint \oint...
5. Determining the final velocity and acceleration magnitude traveling along an arc

Oh! I see, because its a function of distance? So would ads = vdv be more appropriate? My "v" came from the constant acceleration formula but since it isn't constant, this will not work. The speed at A is 40 m/s? EDIT: Wait I figured it out! Since acceleration isn't constant and we're given...
6. Determining the final velocity and acceleration magnitude traveling along an arc

Can this be moved to introduction physics homework help forum? I think its better suited for there, even though this from an Engineering Dynamics textbook. EDIT: Thank you!
7. Determining the final velocity and acceleration magnitude traveling along an arc

Problem Statement: The motorcycle is traveling at 40 m/s when it is at A. If the speed is then decreased at v'=-(0.05s)m/s^2, where s is in meters measured from A, determine its speed and acceleration when it reaches B. I attached a picture of the problem. Relevant Equations: S = S_0 + v_0(t)...
8. Medical What causes the risks of taking steroids?

I appreciate the time you took to post this, this is very informative!
9. Medical What causes the risks of taking steroids?

If that’s the case, what’s your opinion on multivitamin tablets? I just looked at a bottle of multivitamins that I have (‘Opti-Men’). It says 3 tablets a day is one serving, and one serving contains 37.5 mcg of Vitamin D.
10. Medical What causes the risks of taking steroids?

Interesting, I was taught that exercising regularly has great benefits such as decreasing LDL and then to find out that taking steroids actually increases it. I wasn’t informed by anyone about steroids, just surfing the web for quick articles. When I was in high-school, we covered the risks of...
11. Medical What causes the risks of taking steroids?

I understand that anabolic steroids are a synthetic modification of testosterone, the natural body hormone. My question is, are the risks of taking steroids caused by defects in synthesizing the hormone or is it because of how the human body works to counteract the effects of adding more...
12. Can water vapor go directly into a solid

This graph should help you out. Of course, for water to freeze to a solid state it has be at 0* Celsius but that’s just half the puzzle. The atmospheric pressure has to be below 0.006 atm for it to go directly to a solid state instead of it at its triple point (where its solid, liquid, and gas...
13. Studying What Should I Do If My Professors Don’t Teach?

I’ve had success in reading the textbook before hand and then watching online lectures from MIT OCW or professors off of Youtube if something seems to dense for me to understand. It won’t be easy since it’ll be completely based off of how much work you put in yourself. If you still don’t...
14. Specific Heat Problem, not getting the correct answer

So... Substituting the entire formula: CMΔT(copper) + CMΔT(water) = -CMΔT(iron) I know that ΔT of copper and water should be the same and I want to get all the T(final) all on one side: ΔT(CM(copper) + CM(water)) = -CMT(final, iron) + CMT(initial, iron), and from here, I split up the ΔT of...
15. Specific Heat Problem, not getting the correct answer

So the equation should be like this? ΔQ(copper) + ΔQ(water) = - ΔQ(iron)
16. Specific Heat Problem, not getting the correct answer

Homework Statement A copper pot with a mass of 0.500 kg contains 0.170 kg of water, and both are at a temperature of 20.0°C. A 0.250-kg block of iron at 85.0°C is dropped into the pot. Find the final temperature of the system, assuming no heat loss to the surroundings. Homework Equations Q =...
17. Radius of largest possible loop of an Airplane.

Homework Statement A 2250 kg airplane makes a loop the loop (vertical circle) at a speed of 320 km/hour. Find (a) the radius of the largest circular loop possible and (b) The force on the plane at the bottom of this loop. Homework Equations F = m*a Centripetal Force = m * (v2)/r "Critical...
18. Projectile motion HW check

Though we used the range of 3m in the y direction, realistically, the ball would have hit the post and bounced off but we neglected that while we worked the problem out.
19. Projectile motion HW check

Nevermind, figured it out after reading part of my textbook. Thanks for the help guys.
20. Projectile motion HW check

When my professor worked it out, he did the exact same thing. Question though, how did you get ##t = T_1 \equiv 2 v_y/g##?
21. Projectile motion HW check

Yes, here's the worksheet.
22. Vector components

If it were from the x-axis, then the angle would be 57.1°
23. Projectile motion HW check

I think I found my answer but I'm not proud of it because I used parts of what someone else did on chegg.com but I understand the method. velocity in the x-direction: x = v(t) substitution x = (vcos40°)t plugging in the total distance from the problem.. 42m = (vcos40°)t bringing the t to the...
24. Free-fall problem check

This is very true, I just check both equations and got the same thing. Having the units cancel out helps.
25. Free-fall problem check

Thanks for your help, the answer seems so simple to achieve with just some critical thinking. I think I've just been spoon-fed so much to the point that I don't see the simple things anymore!
26. Free-fall problem check

Whoops, used -30m instead of -55m. It's not that I wanted to look up my answers, I just didn't trust my arithmetic and I wanted to see how the proper formula was achieved. The correct answer should be 30.6m/s or 31 m/s.
27. Free-fall problem check

Looking it up online, the proper equation should have been v0 = (Δy/t) - (at/2). Looks like instead of multiplying the constant of 2 like I did, they just inversely subtracted the +½(-9.81m/s2)(t2). For future experiences, I should just inversely bring over variables that have a constant in...
28. Projectile motion HW check

Wow, that completely slipped my mind. I wouldn't think the height of the ball reaches 3m since that's the height of the goal post, it would actually hit it if that were the case. How would I got about finding the correct height? I hope it's not something arbitrary..
29. Free-fall problem check

Okay, so he's what I did starting from the beginning.. I used 2 reference points for stone 1, one at the moment the stone is throwing upward with an initial velocity I need to find and the second one being at the point the stone reaches it's highest maximum height and falls to the ground. Stone...
30. Projectile motion HW check

When you say to use the goal post height and the angle of kick, finding the hypotenuse of the right triangle (assuming that the ball goes in a diagonal line)?
31. Projectile motion HW check

I thought the total distance was 42m (in the x-direction)?..
32. Projectile motion HW check

It's not included anywhere since I just mainly used y components to find the velocity.
33. Free-fall problem check

step numbers are shown by pink pen, my work is all over the place lol... please let me know if it's too messy to understand and I'll rewrite everything more organized!
34. Projectile motion HW check

Picture of my work
35. Free-fall problem check

I apologize, I will try to upload a photo of my work with the steps when I get the chance sometime soon.
36. Projectile motion HW check

Homework Statement A football is kicked from the ground at an angle of 40° to the ground. It travels 42m and just passes over the goal post which is 3m high. What was the inital velocity of the football? Homework Equations vfinal2 = vinitial2 +2a(yfinal-yinitial) The Attempt at a Solution...
37. Free-fall problem check

What about it? I applied it to my calculations and got an initial velocity of ≈ 83m/s? That doesn't sound right to me..
38. Free-fall problem check

yf-yi = vinitial(t)+½at2?
39. Free-fall problem check

Yeah it messes me up too sometimes since everyone else uses vf but my professor uses v1 and v0 instead so that's where I got the habit. I edited post #3.
40. Free-fall problem check

Whoops, forgot to put in t after initial velocity, I included it in my calculations I just realized that if the stone was thrown upward, it wouldn't travel 55m down because the roof itself is 55m above the ground. How would I go about finding the correct position? EDIT: Instead of making y0 =...
41. Free-fall problem check

Homework Statement A man stands on the edge of a roof 55m above the ground, he throws a stone upward and drops a second stone at the same time. If the dropped stone hits the ground 4.4s before the stone that was thrown upward, what was the initial velocity of the first one? Homework Equations...
42. Constant acceleration problem

I know how a relativity is important but my professor never taught us how to use it in any class demonstration nor has he told us to create some sort of equation. I have another 2-D projectile motion problem and also a free-fall problem that I don't understand either. Should I make another...
43. Constant acceleration problem

Oh wow, that would have required a lot of critical thinking out of me. It seems so simple now.. thanks for the help guys!
44. Constant acceleration problem

Whoops, divided by 14m instead. So the answer was t=2.55s? That's the same thing I got when I did it on the napkin.

2.52s?
46. Constant acceleration problem

Well if they're both moving at the same speed, it would look like the car isn't moving. While the car's accelerating, then.. (currently out atm!) ?
47. Constant acceleration problem

This I'm not sure of

49. Constant acceleration problem

Well if the truck were stationary, it would take 0.45s to get the car's rear bumper 14.4m or in front of the truck. Using that time, the truck while moving, at 0.45s, will have traveled another 11.7m? 11.7+14.4m= 26.1m and I use that as the x distance that the car needs to travel all together...
50. Constant acceleration problem

But the car want's to reach 14.4m and that would be his xfinal and the Δx is 12m? The cars velocity and trucks velocity are both 26m/s? I apologize if I'm being dense, I'm use to question that we've done in class and this wasn't one of them.