Maybe a silly question but on the above question using the conservation of momentum:
momentum before firing (0) = momentum after firing (55*35)+(M*2.5)
If I re-range the above it's M = -(55*35)/2.5 = -770kg. I can I reconcile that minus sign (basically get rid of it)?
Thanks
I want to solve this using difference equation. So I set up the general equation to be
Pi = 0.5 Pi+1 + 0.5 i-1
I changed it to euler's form pi = z
0.5z2-z+0.5 = 0
z = 1
since z is a repeated real root
I set up general formula
Pn = A(1)n+B(1)n
then
P0 = A = 1
PN = A+BN = 0 -> A= -BN...
I know that the eigenstates of momentum operator are given by exp(ikx)
To construct a real-valued and normalized wavefunction out of these eigenstates,
I have,
psi(x) = [exp(ikx) + exp(-ikx)]/ sqrt(2)
But my trouble is, how do I find the expectation value of momentum operator <p> using this...
Hi folks, a question regarding the value of G, has there been an experimental data collected on the value of G over time, what I'm interested in, is if the value of G in the observable universe, is decreasing or increasing (by a small amount) over time, thanks.
Hey! :giggle:
Let $X$, $Y$ and $Z$ be independent random variables. Let $X$ be Bernoulli distributed on $\{0,1\}$ with success parameter $p_0$ and let $Y$ be Poisson distributed with parameter $\lambda$ and let $Z$ be Poisson distributed with parameter $\mu$.
(a) Calculate the distribution...
The expectation value of the kinetic energy operator in the ground state ##\psi_0## is given by
$$<\psi_0|\frac{\hat{p^2}}{2m}|\psi_0>$$
$$=<\psi_0|\frac{1}{2m}\Big(-i\sqrt{\frac{\hbar mw}{2}}(\hat{a}-\hat{a^{\dagger}})\Big)^2|\psi_0>$$
$$=\frac{-\hbar...
There are 8 items in a data set. The sum of the items is 48.
a. Find the mean.
$\qquad\textit{mean}=\dfrac{\textit{sum}}{\textit{data set}}=\dfrac{48}{8}=\textbf{6}$
The variance of this data set is 2. Each value in the set is multiplied by 3.
b. Write down the value of the new mean.
$\qquad...
Hey! :giggle:
Let $f(x)=e^{-x}\sin (x)$, $x\in \mathbb{R}$.
a) Calculate the Taylor polynomial of order $4$ at $0$.
b) Calculate the value of $f \left (\frac{1}{2}\right )$ using estimation for the remainder with an error not more than $\frac{1}{400}$.I have done question a) ...
When I run this simple code:
int main() {
int x = 45;
std::unique_ptr<int> q(new int (x));
*q = 3;
cout << x << endl;
}
45 is printed on the console. I expected this to print 3 to the console. It prints 3 when I use a built-in pointer. Does this mean that unique pointer...
A recent thread by @coolcantalope was accidentally deleted by a Mentor (I won't say which one...), so to restore it we had to use the cached version from Yahoo.com. Below are the posts and replies from that thread.
The cached 2-page thread can be found by searching on the thread title, and is...
Here is my attempt at a solution
I don’t know where to go from here, as the equation is a quadratic it will have two solutions which means there will be two stationary points, but I don’t know how to solve for z.
Hi, I'm currently a Grade 11 student and I need help for this question (Precalculus):
If $\sum\limits_{i=1}^{50} f(i)=90$ and $\sum\limits_{i=30}^{50} g(i)=60$, what is the value of $\sum\limits_{i=1}^{50} (7 g(i)-f(i)+12)/(2)$?
P.S. To those who could answer this, it would be a great help...
I was trying this problem from some 2 hours but unable to crack it. I cannot proceed after few lines i.e$${\frac{axsin\theta}{cos^2\theta}} - {\frac{bycos\theta}{sin^2\theta}} = 0$$ $${\frac{axsin\theta}{cos^2\theta}} = {\frac{bycos\theta}{sin^2\theta}}$$ $${\frac{ax}{by}}...
First thank you for taking your time to take a look at this simple question. And sorry for the informal math language and equations, I hope you guys can understand it.
So, depending on the case, I have 2 or 8 simple quadratic functions f(a), f(b), f(c),… f(z).
Each a,b,c,…,z have a different...
If $\alpha,\,\beta,\,\gamma$ are the roots of the equation $x^3+ax+1=0$, where $a$ is a positive real number and $\dfrac{\alpha}{\beta},\,\dfrac{\beta}{\gamma},\,\dfrac{\gamma}{\alpha}$ be the roots of the equation $x^3+bx^2+cx-1=0$, find the minimum value of $\dfrac{|b|+|c|}{a}$.
from numpy import log as ln
z = 3
k = 2
x = 1 - ln(1 + z) / ln(1 + k)
y = 1/5
print("The x=", x)
Q = x**y
print(Q)
The result is
The x= -0.26185950714291484
c:\Users\-\Desktop\... RuntimeWarning: invalid value
encountered in double_scalars
Q =...
I found, what appears to be, a good channel on General Relativity and other science topics.
I'm dubious because... the internet.
I'd love a second opinion on whether this channels first few videos on The Maths of General Relativity are doing it justice.
I'm a dad with a day job and I can't...
In the example below, x is static while x1 is a dynamic copy of x. Also, y and z are similar expressions containing x and x1 respectively.
If we evaluate expressions containing x and x1, they display in numeric and mathematical formats, respectively (y and z below). How can I display z as a...
it really took me time to figure out as to how that equation in aterisk was arrived at...i just noted that both sides of the equation were multiplied by ##-\frac {1}{3}## any particular reason for that? what is the common thinking around that? can one multiply both sides by say ##\frac {1}{6}##...
For Example:
Trial 1: 5.36 ± 0.03
Trial 2: 5.42 ± 0.04
Trial 3: 5.35 ± 0.01
Trial 4: 5.38 ± 0.03
Trial 5: 5.45 ± 0.02
What I did was take the average of the best estimates and the uncertainties.
Best Value 5.39 ± 0.03
(0.03+0.04+0.01+0.03+0.02)/5=0.026=0.03
Let $a,b,c, \tau$ be positive constants and $x$ is an exponentially distributed variable with parameter $\lambda = 1$, i.e. $x\sim\exp(1)$.
\begin{equation}
E = \tau\Big[a\frac{1+a}{1+e^{-bx+c}} - 1 \Big]^+
\end{equation}
where $[z]^+ = \max(z,0)$
How can I find
The PDF for $E$
The...
The source of the 0.824×10-4 value is
http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/denpar.html .
I also looked at the Planck 2018, paper I but could not find a value for Ωr. I searched the internet with:
radiation density cosmology friedmann omega
but I had no success. I also looked at...
##\int_0^5 [-x^3+3x^2+6x-8\,]dx##
##\int_0^1 [-x^3+3x^2+6x-8\,]dx= |-\frac {17}{4}|##
##\int_1^4 [ -x^3+3x^2+6x-8\,]dx= 16##
##\int_4^5[-x^3+3x^2+6x-8\,]dx= |-\frac {49}{4}|##
Therefore, total area is ##|-\frac {17}{4}|+ 16+|-\frac {49}{4}|=32.5##
now where my problem is,... my colleague...
I may have misunderstood the expectation value, but if not then with the Copenhagen Interpretation it is easy to understand the expectation value for a wave function. It is just based on the probability of each event. If there were 4 possible events, and the probability of the event having a...
Hello everyone, I have to find an interval of this Riemann integral. Does anybody know the easiest way how to do it? I think we need to do something with denominator, enlarge it somehow. My another guess is the integral is always larger than 0 (A=0) because the whole function is still larger...
(1) For ##x>a##
##f(x)=x^2+x-a+1 \rightarrow## minimum value obtained when ##x=-\frac{1}{2}##
Minimum value of ##f(x)=\frac{3}{4} -a##
(2) For ##x<a##
##f(x)=x^2-x+a+1 \rightarrow## minimum value obtained when ##x=\frac{1}{2}##
Minimum value of ##f(x)=\frac{3}{4}+a##
But the teacher said...
##\frac {7}{2x+2}=\frac {4x-3}{-2x-2}##
##-7(2x+2)=(4x-3)(2x+2)##
##x^2+2x+1=0##
##x=1## or ##x=-1##
can we also have;
##-7=4x-3## can the ##2x+2## cancel out? i am a bit mixed up on this very simple problem...and why am i getting false on my ti nsipre...
In the 3rd edition of the Introduction to Quantum Mechanics textbook by Griffiths, he normally does the notation of the expectation value as <x> for example. But, in Chapter 3 when he derives the uncertainity principle, he keeps the operator notation in the expectation value. See the pasted...
I have managed to find the gamma value using the following equation: (T2/T1)= (P2/P1)(gamma-1/gamma. This will give me the answer of 1.29 SF. After this step, I am clueless.
Can someone help me with this question please?
I assume we have to find the enthalpy at state 1 to do that question.
If the boundary condition is not provided in the form of electric potential, how do we solve such problem?
In this case, I want to use ##V = - \int \vec{E} \cdot{d\vec{l}}##, but I don't know how to choose an appropriate reference point.
Hey all,
So this time I have a different kind of question - namely, "what is this called?"
I recall hearing/reading this in at least two places, one of which was YouTube. The idea is the following:
A RNG picks an integer uniformly from 1 to N. It picks 4. What is the expected value of N?
I'm...
Determine an interval in which the solution of the given initial value problem is certain to exist
$t(t-4)y'+y=0 \quad y(2)=2\quad 0<t<4$
ok my first step was isolate y'
s
$y'=-\dfrac{y}{t(t-4)}$
not sure what direction to go since we are concerned about an interval
This confusion has lingered in the back of my mind for years now, would be good for me to finally get a grasp on this.
Say I have an object currently at rest, and I use energy X to accelerate it to speed v. According to the standard formula, it now has a kinetic energy 1/2mv^2.
Now I use the...
I am quite confused by this. I was sure that ω=3*sqrt(5)*10^6, because that is the coefficient of t, and generally u(x,y,z,t)=Asin(kx−ωt+ϕ) for a multi dimensional harmonic wave.
However in the answers it is said that ω=3*sqrt(5)*10^14. I can't see the reason for that, could anyone explain please?
1. When n=1,
u1+1=3-1/3(u1)
u2=3-1/3(3)
u2=2
When n=2
u2+1=3-1/3(u2)
u3=3-1/3(2)
u3=7/3
When n=3
u3+1=3-1/3(u3)
u4=3-1/3(7/3)
u4=20/9
The common ratio is defiend by r=un+1/un, but this is different between the terms, i.e. u2/u1=2/3 whereas u3/u2=(7/3)/2=7/6
Have I made a mistake?
2. A...
Hi all
Simple question: How I can compute the value of \(a = \sin \left( 2017 \sqrt[5]{2} \right) \) under following assumptions:
No use of advanced numerical libraries is allowed.
Only accepted operations are: comparisons, absolute value, addition, subtraction, multiplication and division...
In this text they are saying that rms value is square root of average value of i² but i am not able to relate this thing to equations they have given.
It feels to me that the equations tell something different from the text.
From text I interpret that if we add each and every value of i² from 0...
I tried to do it by derivative but there are two variables, so I don't know how to proceed. Does anyone know how I can solve it?
Remembering that you don't need to find the value of ##\theta##. I just need to find a relationship between ##\theta_1## and ##\theta_2##
If the Summary is not clear, the following is an example translated from: https://telecombloger.ru/7335
'... air conditioning systems. For example, the efficiency of a compressor is about 85%. The remaining 15% is spent on friction, oil movement, overflows, heating, etc. The efficiency of the...
The principal equilibrium in a solution of NaHCO3 is
HCO3-(aq) + HCO3-(aq) <-> H2CO3(aq) + CO32-(aq)
Calculate the value of the equilibrium constant for this reaction.
My solution:
This overall reaction is the same as the sum of the following reactions:
HCO3-(aq) <-> H2CO3(aq) + OH-(aq)...
Question:
The national price of a good is distributed normally with mean £1.20, standard deviation 5p. Sample data is for price in London, determine whether there is sufficient evidence at 5% level to suggest that the mean price in London is different to the national mean. Standard deviation...
Hi
In the book, "Why does E= mc2" by Cox and Forshaw, while discussing time dilation, the example of a muon is given. The authors explain that muons when circulated in the 14 m diameter AGS facility at Brookhaven at 99.94% of the speed of light, its lifetime is increased from the value of 2.2...