The Physics Behind "Fanning The Flames"?
So no one in class knew the answer and, of course, I don't know the answer (that's why I come to the geniuses on this board) :smile:. The question was:
Explain why blowing on a fire may make it burn better.
I'm pretty sure it has something to do...
A helicopter has 4 rotor blades attached to the central axis of rotation. (Like a + sign with the axis of rotation at the center.)
Each rotor blade is 5.2m long and spins at 6 revolutions per second perpendicular to the Earth's magnetic field of 0.047T. What is the emf induced between the...
When using the equation E = hf to find the energy of a photon, do I convert the energy and Planck's constant so they contain the same energy unit? So if I use eV for energy, I convert Planck's constant to eVs? If so, then Planck's constant would be about 4.14(10^-15)eVs? Thanks for the help...
A 120kg astronaut stands on the surface of an asteroid of radius 600m. The astrunaut leaves the surface with 15J of kinetic energy and reaches a maximum height of 300m above the surface. What is the mass of the asteroid? (Answer: 3.4*1012kg)
At the maximum height, all of the kinetic energy...
Yep, I copied these questions exactly as they were stated in my workbook.
Werg22, I don't understand your explanation. I'm saying that positive is up and negative is down. 0 = 420-490+Fc. Fc has to be positive 70N which means its up. I don't think there's anything wrong with the algebra...
1. Which of the following statements best applies to an object moving with uniform circular motion?(Answer: B)
A. Acceleration is zero.
B. Acceleration is directed outward.
C. Acceleration is tangent to the path.
D. Magnitude of acceleration is constant.
I thought the answer was D but how...
Hmm okay I think I understand.
For the sliding down the slope part:
mgh = 1/2mv^2
Then for the loop:
1/2mv^2 > mg(2r) so the ball continues to move when its at the top of the loop
Then:
mgh > mg(2r)
h > 2r
Is that correct?
What do you mean just energy? Sorry I don't understand your response. All I could come up with was mgh = (something), but I don't know what to equate it to.
Hmm I thought I was pretty good at this stuff but I guess not. :mad: I'd really appreciate it if someone could show me how to solve this problem. Does it involve anything more than work, power, and energy concepts?
http://img205.imageshack.us/img205/7159/presentation19ai.jpg
A small...
Hmm I still need help with 1 and 2. I made some pictures to show you what I mean.
http://img376.imageshack.us/img376/8420/volt13pc.jpg
1. If you measured the voltage at point D, would it be 6V?
http://img376.imageshack.us/img376/2395/volt6yn.jpg
2. If you measured the voltage at point...
I need help with the idea of voltage as it relates to electric circuits. My book doesn't explain the concept well enough. All it says is that voltage is the force that moves charge through a circuit and overcomes resistance. Then it just states Ohm's Law, V=IR.
Here are the things I don't...
Oh okay, I see the problem we both made here. We assumed that the final velocity of the ball was equal to the inital velocity but the question didn't state that. Tricky...
Hmm, that's strange. If ∆px = 0, then px` = px but that clearly isn't the case here since the angle of incidence and the angle of deflection are not equal. I don't see how they can make that claim. I'm just as stumped as you are now.
Yes the mass is 6.8kg and the volume is 1liter which is equal to 0.001m^3. The density is mass divided by volume which is 6.8kg/0.001m^3. Do 6.8 divided by 0.001 on a calculator; what answer do you get?