Homework Statement
A metallic chain with a length ‘l’ andd whose ends are joined together is fitted onto a wooden disc as shown in the figure.The disc rotates with a speed of n revolutions per second.Find the tension of the chain T if its mass is m.
Homework Equations
The Attempt at a...
Homework Statement
Show z(x,y) = cos(xy) is a solution of
(∂z/∂x)y + (∂z/dy)x = (x+y) ( (∂2z/∂x∂y) + xyz)
(question also attached if it makes it clearer)
The Attempt at a Solution
∂z= (∂z/∂x)ydx + (∂z/dy)xdy
∂z/∂x = -ysin(xy)
∂z/∂y = -xsin(xy)
what does it mean show it...
hey pf!
suppose i have a function ##f( x , y)##. i make a change of variables such that ##z(x,y)## in such a way that now ##f( z , y)##. how do i find $$\frac{\partial f}{\partial y}$$ $$\frac{\partial f}{\partial x}$$ $$\frac{\partial^2 f}{\partial y^2}$$ $$\frac{\partial^2 f}{\partial x}$$...
Homework Statement
Pls help me with the (d) option of the question asked in the link
https://www.physicsforums.com/showthread.php?t=724332&page=1
Correct expression for tension is ρgx/6 (as given in the answer sheet)
Homework Equations
The Attempt at a Solution...
Homework Statement
Estimate the lifetime of a proton against fusion to 4He in the center of a Zero-Age-Main-Sequence solar mass star. First calculate the energy generation, εpp in the center of the star from the p-p chain. Then convert this to the number of fusions (conversion of 4 protons...
Suppose we have a function V(x,y)=x^2 + axy + y^2
how do we write
\frac{dV}{dt}
For instance if V(x,y)=x^2 + y^2, then \frac{dV}{dt} = 2x \frac{dx}{dt} + 2y \frac{dy}{dt}
So, is the solution
\frac{dV}{dt} = 2x \frac{dx}{dt} + ay\frac{dx}{dt} + ax\frac{dy}{dt} + 2y \frac{dy}{dt}
Hi,
I have a question regarding polymers.
You know that polymers, basically, consist of chains of polymers, each chain including number of repeating units (monomer). These chains can be in amorphous or crystalline states.
Experimentally, is it possible to fabricate and see a single chain...
Homework Statement
Problem: Given C is the graph of the equation
2radical3 * sinpi(x)/3 =y^5+5y-3
Homework Equations
(1) Prove that as a set
C= {(x,y) Exists at all Real Numbers Squared | 2radical3 * sinpi(x)/3 =y^5+5y-3
is the graph of a function differentiable on all real...
Homework Statement
A chain of mass M and length ##\ell## is suspended vertically with its lowest end touching a scale. The chain is released and falls onto the scale. What is the reading of the scale when a length of chain, ##x##, has fallen? (Neglect the size of individual links.)...
Homework Statement
Suppose f is differentiable on \mathbb R and \alpha is a real number. Let G(x) = [f(x)]^a
Find the expression for G'(x)
Homework Equations
I'm pretty sure that I got this one right, but I really want to double check and make sure.
The Attempt at a Solution...
Homework Statement
here's the question, is my concept correct? the ans is 9.86 cm, but my ans is 13 cm, can anyone tell me which part is wrong?
Homework Equations
The Attempt at a Solution
Homework Statement
If possible, please check my work for any large errors.
y = 10kl - √k - √l
k = (t/5) + 5
l = 5e^t/10
Evaluate at t = 0 using chain rule.
Homework Equations
y = 10kl - √k - √l
k = (t/5) + 5
l = 5e^t/10
The Attempt at a Solution
= ∂y/∂k * dk/dt + ∂y/∂l * dl/dt
= (10l -...
Homework Statement
I am confused because for each problem there is no equation and for one no intermediate variables.
Compute dy/dt when
a) y = f(t, t^2, t^3)
b) y = g(t, h(t), k(t^2))
Homework Equations
a) y = f(t, t^2, t^3)
b) y = g(t, h(t), k(t^2))
The Attempt at a...
Hello all,
I need some help with this chain rule problem.
\[F(x,y)=f\left (\frac{x-y}{x+y} \right )\]
It is known that:
f'(1)=20,f'(2)=30, f'(3)=40
and
\[f''(1)=5,f''(2)=6,f''(3))=7\]Find
\frac{\partial F}{\partial x}(2,-1)
and
\[\frac{\partial^2 F}{\partial x\partial y}\]The final...
is there any way to add power of two independent chain drives having different rpm , such that slipping doesn't occur and driven shaft move with the added resultant power
Energy Question -- Chain sliding off frictionless table
Homework Statement
Here is the problem that's confusing me: A frictionless chain of length 2.00m is held with 20.0% of its length hanging over the edge of a table. The chain is then released. Determine its speed the moment the entire...
I have no idea how to solve this. All i can think of is that you need mass to solve the problem.
Homework Statement
A chain is lying flat on a table. It has no friction against the flat surface. You pull the chain to the edge of the table so that it from a resting state starts to slide down...
I'm randomly having trouble applying the chain rule to functions (well, 1 function in particular), I was hoping someone could quickly walk me through this simple problem as I don't know where I've gone wrong. I've tried U substitution, chain/product rule, factoring answer...but I just can't see...
Differentiate the following by rule y=(2x2+4x)5
Is the chain rule the right rule to use?
dy/dx=dy/du*du/dx
Let U=2x2+4x
du/dx=4x+4
y=(u)5 → dy/du=5(u)4
dy/dx=5(u)4*4x+4
dy/dx=5(2x2+4x)4*4x+4
dy/dx= 30(2x2+4x)44x
dy/dx= 30(2x216x)4
I'm wondering if I am on the right...
Dear all,
I was wondering how the radii of curvature can be calculated of a flexible chain (polymer chain). I have the x,y and z values of the polymer chain. For a 2D chain, I can calculate the curvature radii (http://www.intmath.com/applications-differentiation/8-radius-curvature.php). I am...
Homework Statement
A chain with length ℓ is held stretched out on a frictionless horizontal table, with a length y0 hanging down through a hole in the table. The chain is released. As a function of time, find the length that hangs down through the hole (don't bother with t after the chain...
Homework Statement
A chain is wrapped around a disk of radius R. The tension of chain is T. What is the coefficient of friction, if when the disk is spinning at angular velocity ω, the chain slips down?
See image attached.
Homework Equations
II Newton law
a_{centripetal} =...
Let $z:\mathbb{R}^2\to \mathbb{R}$ an function of kind $C^2(\mathbb{R}^2)$. What transforms the equation $2\dfrac{\partial^2 z}{\partial x^2}+\dfrac{\partial^2 z}{\partial x\partial y}-\dfrac{\partial^2 z}{\partial y^2}+\dfrac{\partial z}{\partial x}+\dfrac{\partial z}{\partial y}=0$ under the...
Hello,
I need to do this proof here:
I tried but didn't get what I wanted, so I was re-thinking the whole thing.
If I say u=y+ax and v=y-ax, should I do something like (dz/df)*(df/du)*(du/dx)+...?
Because I tried just with u and v (without f and g), and I got almost what I wanted, with a...
Hello all,
I have a problem with second derivatives and chain rule.
I am working on the question attached (sorry, my Latex editor wasn't working...)
I need to find F'(1) and F''(1). I managed to solve F'(1), but I can't figure out F''(1). In the second image attached, you can see the solution...
Homework Statement
Homework Equations
The Attempt at a Solution
I am not sure how to proceed with the given problem. I can write down the net force on any of the charges but what should be the condition that the chain breaks? :confused:
Any help is appreciated. Thanks!
Hello everyone,
I am reading a proof of the chain rule given in this link: http://kruel.co/math/chainrule.pdf
Here is the portion I am troubled with:
"We know use these equations to rewrite f(g(x+h)). In particular, use the first equation to obtain
f(g(x+h)) = f(g(x) + [g'(x) + v]h)...
Hi fi you look at quesiotn 16b in the following link they try to find dE/dx.
they use the chain rule. the chain rule says dF/dt=dx/dt*dF/dx+dy/dt*dF/dy if F=f(x,y) and x=f(t) and y=f(t).
But in 16b they're trying to find dE/dx and as part of the use of the chain rule they try to find...
Hi, I’m a bit confused.
I am familiar with the chain rule: if y=f(g(t,x),h(t,x)) then dy/dt=dy/dg*dg/dt+dy/dh*dh/dt
To show that an equation is invariant under a galiliean transform, it’s partially necessary to show that the equation takes the same form both for x and for x’=x-v(T). So if you...
Hey! :o
Given the Markov chain $\{X_n, n \geq 1\}$ and the following probability transition matrix:
$\begin{pmatrix}
0 & 1/3 & 2/3\\
1/4 & 3/4 & 0\\
2/5 & 0 & 3/5
\end{pmatrix}$
All states communicate, so the chain is irreducible, isn't?
Could you tell me if the state $2$ is periodic?
Hello everyone, first post here.
Homework Statement
Let f(x,y)=x2y+y2x , where x=sin2t
and y=cos2t.
Use the chain rule to compute df/dt
Homework Equations
f(x,y)=x2y+y2x
x=sin2t
y=cos2t
The Attempt at a Solution
This is pretty much the exact wording of the question...
I'm not entirely sure if this belongs in homework or elsewhere -- I'm self-teaching working through a basic calculus text, so it's not homework per se. In any case it's a simple differentiation problem wherein I am supposed to differentiate:
f(x) = x(3x-9)^3
f'(x) = 3x(3)(3x-9)^2 Applying...
How do I compute the following differentiation by chain rule?
\frac{d}{d\lambda}(\lambda^{-1}\phi(\lambda^{-1}x))
It is not a homework, but I can't figure out the exact way of getting the answer -\phi(x)-x^{s}\partial_{s}\phi(x)
Homework Statement
You are lifting a chain straight up at a constant velocity v_0. The chain has a linear mass density λ. What is the force required to lift the chain as a function of height?
The Attempt at a Solution
U = mgh = λygh
The height in the potential energy is the same as...
Homework Statement
One end of the chain falls through a hole in its support and pulls the remaining links after it in a steady flow. If the links which are initially at rest, acquire the velocity of the chain suddenly and without frictional resistance or interference from the support or from...
Homework Statement
We have a chain of 10 blocks, all of them joined by a thin rope and placed in a straight line.
Suddenly, other two blocks collide with v speed at one end with the chain of the 10 blocks.
It is assumed that the table is frictionless and the collision is elastic.
The main...
Homework Statement
Let h(u,v) = f(a(u,v), b(u,v)), where a_u = b_v and a_v = -b_u.
Show that h_{uu} + h_{vv} = (f_{xx} + f_{yy}) (a^2_u + a^2_v).
Homework Equations
The Attempt at a Solution I suppose my first question is where the x's and y's come from. (I thought at first it...
Homework Statement
Show that any function of the form
##z = f(x + at) + g(x - at)##
is a solution to the wave equation
##\frac {\partial^2 z} {\partial t^2} = a^2 \frac {\partial^2 z} {\partial x^2}##
[Hint: Let u = x + at, v = x - at]
2. The attempt at a solution
My problem with this is...
Take \(U(\eta) = u(x - ct)\) and the wave equation \(u_{tt} - u_{xx} = \sin(u)\). Then making the transformation, we have
\[
(1 - c^2)U_{\eta\eta} = \sin(u).
\]
My question is the chain rule on the differential.
\[
U_{\eta} = \frac{\partial u}{\partial x} \frac{\partial x}{\partial\eta} +...
Homework Statement
Find the second derivative of $$9x^2+y^2=9$$
Homework Equations
Chain rule
The Attempt at a Solution
I find the first derivative first.
$$18x+2y\frac{dy}{dx}=0$$ $$\frac{dy}{dx}=-9\frac{x}{y}$$
I then find the second derivative...
Homework Statement
Find the derivative of $$y=cos(\frac{1-e^{2x}}{1+e^{2x}})$$
Homework Equations
Chain rule
The Attempt at a Solution
$$y=cosu$$ $$\frac{dy}{du}=-sinu$$
$$u=\frac{1-e^{2x}}{1+e^{2x}}$$ $$ \frac{du}{dx}=(1-e^{2x})(-(1+e^{2x})^{-2})+(1+e^{2x})^{-1}(-2e^{2x})$$...
Homework Statement
Find the derivative of y=cos(a3+x3)
Homework Equations
Chain rule
The Attempt at a Solution
y=cosu
\frac{dy}{du} = -sinu
u=a3+x3
\frac{du}{dx} = 3a2+3x2
\frac{dy}{dx} = -3sin(a3+x3)(a2+x2).
The answer is supposed to be -3x2sin(a3+x3). What did...
Homework Statement
Find the derivative of y=xe-kx
Homework Equations
Chain rule
The Attempt at a Solution
y = xeu
\frac{dy}{du} = xeu+eu
u = -kx
\frac{du}{dx} = -k
\frac{dy}{dx} = (xe-kx+e-kx)(-k)
= e-kx(x+1)(-k)
= e-kx(-kx-k)
The answer is e-kx(-kx+1)...
Hi, I have a test prep question regarding Chain Rule, please see the problem and my attempt below. I believe part A is okay but part B, I'm just confused, seems like there is a part missing from the question, or at least how I'm use to doing it.
Homework Statement
A. Let f(x, y) =...
If ##r## is a function of ## x,y##, then
\delta r= \frac{\partial r}{\partial x}\delta x + \frac{\partial r}{\partial y}\delta y
Means
Small change of r = ##\left[\frac{\partial r}{\partial x}\right]_{y=k}## X (Small change of x) + ##\left[\frac{\partial r}{\partial y}\right]_{x=k}## X...
Homework Statement
Solve d^2x/dt^2 = (3x^3)/2
when dx/dt = -8 and x = 4 when t = 0
2. The attempt at a solution
v = dx/dt dv/dx = d^2/dx^2
d^2x/dt^2 = v(dv/dx) = (3x^3)/2
v dv = (3x^3)/2 dx
integrating and using limits and you get :
v^2/2 -32 = (3x^4)/8 - 96 ...
Homework Statement
A chain of three links, each with a mass 0.2 kg, is being pulled up by a person lifting the top link with 8.88 N of force and the chain accelerates upward. Calculate three forces that are acting on the middle link while the chain is accelerating.
Homework Equations
ƩF = ma...
Homework Statement
Solve (d^2x)/(dt^2) = 2x(9 + x^2) given that dx/dt = 9 when x = 0 and x = 3 when t = 0
Homework Equations
The Attempt at a Solution
v = dx/dt ...... dv/dx = d^2x/dt^2
dv/dx = v(dv/dx)
v(dv/dx) = 18x +2x^3
integrating and evaluating using...