Homework Statement
A stone is dropped of a cliff. A second stone is thrown down the cliff at 10 m/s at 0.5s after the first stone. When do the stones cross paths?
Homework Equations
Yf = vt + at^2/2
The Attempt at a Solution
My logic is the set the final position Yf equal for both stones...
Yep, got it. I was on the wrong track. . . I would shoot myself in the foot, but instead I may get rid of it altogether!
Thanks for the help and quick replies.
Getting rid of time; the only way I see that is if I substitute t = \frac{x_f}{v_x} , giving us
y_f = x_f tan(\theta) + \frac{1}{2 v_x^2} a_y x_f^2.
Perhaps I do not understand, we do not know y_f , nor x_f .
I tried this but here is what I got: y_f = x_f tan(\phi - \theta) + \frac{1}{2}a_y t^2. Still too many unknowns though, assuming my algebra and logic is correct of course.
Homework Statement
I was tutoring the other day, when we came across a problem that had me stumped!
A person standing on a hill that forms an angle \theta = 30^o wrt to the horizon, throws a stone at {\bf v} = 16 m/s up the hill at an angle \phi = 65^o wrt to the horizon. Find y_f...
Hello, this is probably one of those shoot yourself in the foot type questions.
I am going through Landau & Lifshits CM for fun. On page 7 I do not understand this step:
L' = L(v'^2) = L(v^2 + 2 \vec{v} \cdot \vec{\epsilon} + \epsilon^2)
where v' = v + \epsilon . He then expands the...
Okay, also note that \int \cdots \int f(\vec{x}) \delta(\vec{x} - \vec{x}_o) d^Nx = f(\vec{x}_o). This can allow you to fix some variables.
My next question is, are we integrating from -\infty \rightarrow \infty ? If the variable being integrated is not within the bounds, we can simplify...
For increasing frequency, the number of nodes will increase as well. Draw several diagrams, double the frequency each time. Then you can deduce how frequency affects the nodes and antinodes.
Hmm, perhaps forget what I mentioned previously. You simply need to reconsider your wave function. Perhaps try something of the form \psi = e^{\pm i(kx-E t/ \hbar)} . . .
Perhaps, we can treat this similar to the case for an infinite wire? Are we finding the E-field at some point say on the y-axis, or some point on the x-axis?
Must we use Gauss's Law?
Yes, really what we have is a point charge in one dimension, where we only consider the charge density along the x-axis. I suppose a cylinder would be fitting for Gauss's Law. Yes, you are correct about integrating along the x-axis.
Is x a vector? If not, assume one dimension. Your surface area will most likely be of a sphere. Also, recall that q_{enc} is the total charge. Can you think of another (more formal) way to write q_{enc} ?