Recent content by eigenglue

pi is equal to the natural logarithm of -1 divided by the square root of -1.

Ok for a washer the area is pie(r1^2 - r2^2), where r1 is the larger radius and r2 is the smaller radius. So I think you just need to take a closer look at which is the larger and smaller radius and remember to square them too. OTOH if you used shells you might not have to deal with a square...

Ok first off, if two curves intersect at right angles, then the derivative of one is going to be equal to the negative reciprocal of the other. So if f(x) and g(x) intersect at point a, they interstect at right angles if f'(a)=-1/g'(a). So like if f'(a) is 2, then g'(a) would be -1/2, etc. etc...

That's the correct calculation of acceleration, but the part you did after that was wrong because you should have used the velocity. Moreover they didn't tell you the initial velocity of this object, so what you really want to get the change in kinetic energy is the change in the velocity...

470.4 N is the right weight. Now how much for does it take to push that weight up a 70 degree incline? I think that's the question.

Unless you do something great, they were both smarter than you. That's the answer.;)

check your calculation of the wavelength again: 3.00 X 10^8 m/s = 75 X 10^6 s^-1 X ?m Then, figure out whether the 134m to the plane is a whole number or wavelengths or not, and take into account the wavelength/2 change in phase.

Let u = x^2 + 1 Then du = 2x*dx So x*dx/(x^2 + 1)^(1/2) = du/(2*u^(1/2))

First figure out the weight per area of the aluminum sheet in N/m^2, based the numbers given. That weight per area is then the difference in pressure needed to lift the plate. Assume the air below the plate is still, and figure out how fast the air on top of it needs to be to create the pressure...

How much does 120N make 74kg accelerate? Thats all you need to consider to get the accelaration of the astronaut.

You have an equilibrium point where x has two real values, which would be wherever the term inside the square root is greater than 0. You don't need to set the second derivative to zero. You compare the second derivative to zero to determine whether the points above were minima or maxima...

Draw a vertical line on piece a paper. Then draw an intersecting line downward and to the left at an angle of 45 degrees to the original line. Then draw another line outward from the same intersection point downward and to the right at 30 degrees to the original line. Now the pivot point for the...

For problem 1, isn't (x^2)/((x^4)+1) always less than 1/(x^2) for values of x > 1? For problem 2, what does the integrand approach as x approaches infinity?

The extra assumption is that conservation of momentum holds true in all inertial reference frames. That leads to the to the relativistic mass formula.

To measure time, you need photons of known fixed wavelength, so that you know the frequency. If you are moving in reference to the source, that changes the frequency (doppler effect), but that's not a problem in atomic clocks. So you use a specific atomic vibration, with a specific energy, to...