In mathematics, a ratio indicates how many times one number contains another. For example, if there are eight oranges and six lemons in a bowl of fruit, then the ratio of oranges to lemons is eight to six (that is, 8∶6, which is equivalent to the ratio 4∶3). Similarly, the ratio of lemons to oranges is 6∶8 (or 3∶4) and the ratio of oranges to the total amount of fruit is 8∶14 (or 4∶7).
The numbers in a ratio may be quantities of any kind, such as counts of people or objects, or such as measurements of lengths, weights, time, etc. In most contexts, both numbers are restricted to be positive.
A ratio may be specified either by giving both constituting numbers, written as "a to b" or "a∶b", or by giving just the value of their quotient a/b. Equal quotients correspond to equal ratios.
Consequently, a ratio may be considered as an ordered pair of numbers, a fraction with the first number in the numerator and the second in the denominator, or as the value denoted by this fraction. Ratios of counts, given by (non-zero) natural numbers, are rational numbers, and may sometimes be natural numbers. When two quantities are measured with the same unit, as is often the case, their ratio is a dimensionless number. A quotient of two quantities that are measured with different units is called a rate.
What is ideal lift distribution for propeller blade to get best thrust/power ratio?
To do this blade must has minimum drag, because drag releted to torque,and torque x RPM= power..
Hello, everybody:
I am a philologist who is fond of mathematics, but who unfortunately has just an elementary high school knowledge of them. I am translating La leçon de Platon, by Dom Néroman (La Bégude de Mazenc, Arma Artis, 2002), which deals with music theory and mathematics in the works of...
I was asked to find the ratio of the fluxion of x to the fluxion of 1/x using Newton's synthetic method of fluxions. I do not understand how to do this.
So 7 parts is worth £76 more than 3 parts which means that
4 parts = £76
So 1 part = £19
Therefore Andreas gets £57, Isla gets £38 and Paulo gets £95.
So Andreas has £57 - £48.50 = £8.50 left
Is this correct please?
Hey! :giggle:
Show for each sequence $(a_n)\subset (0, \infty)$ for which the sequence $\left (\frac{a_{n+1}}{a_n}\right )$ is bounded, that $\sqrt[n]{a_n}$ is also bounded and that $$\lim \sup \sqrt[n]{a_n}\leq \lim \sup \frac{a_{n+1}}{a_n}$$ I have done teh following:
The sequence $\left...
Summary:: Direction of reaction A = 2B and we know that there is 70% of products and K = 2.3
Question is: What is the direction of reaction A = 2B and we know that there is 70% of products. K = 2.3
K = B^2 / A
B:A = sqrt (K.A) / A
I have came here but what should I do now? Because when I...
From Wikipedia I have found out that as a cell ages, it's Nucleus shrinks and thus the intial N/C decreases from 4:1 for most cells to 2:1.
I also have a rough idea that Cell machinery becomes unorganised and inefficient.Also high N/C is a characteristic of Cancerous cell.But I do not know the...
According to Wikipedia,
(citation needed)
https://en.wikipedia.org/wiki/Ultraviolet
What would alter this proportion of emitted radiation to favor more 185nm radiation?
Preferably not with a filter that filters out 253.7nm (mathematically would also increase the ratio of radiance of...
I want to plot the ratio f1(x) / f2(x), where they have some common zeros. Does Mathematica have a feature that will do this, switching automatically to f1'(x) / f2'(x) when appropriate, avoiding F.P. errors and optimizing numerical precision?
If not, is there a good way to implement this?
Hi!.. As known, a certain amount of energy is applied for compressing a mechanical spring. Thus mechanical spring is charged with energy and it stores it as elastic-potential energy. But whole energy, applied for compressing spring, can not be converted into potential energy. The reason is...
I found my energies for Potassium. I have 3.3 KeV for the k alpha nd 254.6 ev for L alpha, using z=19 and n=3. Are these values correct?
Edit: I found the ratio to be .077
Hi, I ran into problems using the poisson ratio.
For a FE simulation I created a simple 2D 1mm x 1mm block, and prescribed a 0.1 mm displacement at the top edge.
Furthermore, the bottom edge is constraint in the y-dir, and the left edge in the x-dir.
The material parameters are E = 100, and v...
https://arxiv.org/abs/2010.15621
Superselection of the weak hypercharge and the algebra of the Standard Model
Ivan Todorov
[Submitted on 29 Oct 2020]
I haven't had time to study this paper yet. But a few curiosities:
It talks about Clifford algebras. But in fact it builds on work due to...
Hi,
The Homestake gold mine near Lead,South Dakota is excavated to 8000 feet below the surface. Lead is nearly a mile high; the bottom of the Homestake is about 900 m below sea level. Nearby custer peak is about 2100 m above sea level.
What is the ratio of barometric pressure on the top of the...
Summary:: An image was taken with a ##60## second exposure time of a 6th magnitude star and the signal to noise ratio was detected to be ##S/N = 20##.
a. What should the exposure time be if you wanted a ##S/N = 100##?
b. Now calculate the ##S/N## if it were a 2nd magnitude star for a ##10##...
Hello! Tau decay has a branching ratio to a charged pion + neutral pion + tau neutrino much bigger than to a charged pion and a tau neutrino. Based on consideration of available phase space, I would imagine that adding an extra pion would decrease the branching ratio. Why is this happening...
The question is: If the compression ratio of car engines is increased by 10% (from 10 to 11), estimate the volume reduction in annual CO2 emission. Assume there are 30 million cars each consuming one cubic meter of fuel annually.
The question is looking for a rough estimate for an answer.
I...
Could I please ask for help with the following:
ABC is a right-angled triangle in which AB = 4a; BC = 3a. Forces of magnitudes P, Q and R act along the directed sides AB, BC and CA respectively. Find the ratios P:Q:R if their resultant is a couple.
Book answer is 4 : 3 : 5
Here's my diagram...
Hello, I could use some help learning how to properly size stepper motor.
Suppose that I want to use a stepper motor to move a load against the force of gravity. It must be able to start, stop, and hold it's position against the static load. I know the maximum torque of the load. In addition, I...
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...
Hi. I've been given these sets of value. How do I calculate Young's modulus and Poisson Ratio from these set of value. I tried to create a stress vs strain graph but the graph does not look like a common stress vs strain graph but instead more of a y=x graph.
The diameter of the rod is 10mm and...
As I was looking in the caracteristics of an old tank, I found a number that I could not get anything of on the web. It is called "entire reduction ratio" and was presented just under the gearbox caracteristics. His value is 1:13.4. My question is : is it useful? Does this value have relation...
Hi,
I have a question regarding a practical CMRR calculation.
Main information:
- Signal input: 10 mV rms
- Interference input: 1.5 V rms
- In an earlier part of the question, we found that for the second stage of the instrumentation amplifier (the summation amplifier) that:
$$...
60% of the members of our club are men and the rest were women. When 45 new members joined the club, the number of a female members increased by 50% and the number of men was 1 1/2 times as many as before. how many club members were there initially?
ok from the $ \dfrac{60\%}{40\%}$ ration we...
Sam wants to convert a mixture of acid and water in the ratio 16 : 19 to 19 : 16. What is the amount of acid as a percentage of initial solution that should be added to achieve the required ratio?
I am not sure about my free body diagram. I assume the cylinder rolls without slipping so the forces acting on the cylinder are:
Weight directed vertically downwards
Normal force directed perpendicular to the plane
friction directed upwards, parallel to the plane
Am I correct till this point...
Hello,
I have completed the question below.
I am just unsure on whether i am correct or not.
I am unsure on Mechanical Advantage. As i have seen a few different equations.
Question:
Answer:
a)
Velocity Ratio = $$\frac{\text{Distance Moved By Effort}}{\text{Distance Moved By Load}}$$...
Hello,
I want to understand the difference between both goodness-of-fit tests, I would be glad if you could help me:
Akaike Information criterion is defined as:
## AIC_i = - 2log( L_i ) + 2K_i ##
Where ##L_i## is the likelihood function defined for distribution model ##i## .
##K_i## is the...
A person weighing 60 kg exerts 30 kg of thrust on a pedal (crank) x 2 pedals = 60 kg of force per Revolution. Let's say @ 30 RPM.
What is the output kg of force per RPM on the back wheel where it meets the tar.
I have all the sizes and forces, yet the correct formula eludes me.
The ratio per 1...
I have the solution, but my question is that in my first attempt, I simply calculated a_c = 60^2/150 ignoring the fact that the units for 60 are km/hr and the units for 150 are meters. Is this ever salvageable? Is there any way to retain the 'mixed' units of km with meters in the ratio and...
I could simplify the expressions in the numerator and denominator to (1+x^n)/(1+x) as they are in geometric series and I used the geometric sum formula to reduce it. Now for what value of n will it be a polynomial?
I do get the idea for some value of n the simplified numerator will contain the...
Hi guys,
I'm studying my first-year physics in college, and I'm having to write a report of some proton-proton collisions that were registered in the LHC of CERN years ago. The main goal is to identify different bosons (W and Z) that are decaying into other elemental particles. I've been asked...
I've written out the half reaction
8e- + 9H+ + SO42- = HS- + 4H2O
and I know the logK = 4.25 (that's the constant mentioned in the prompt)
I've written out the equilibrium statement of 10^4.25 = ([x^1/8]*[H2O^1/2])/([10x^1/8]*[e-]*[(10^-8.2)^9/8]
However, from there, it seems like I have two...
I've attached a figure I've made; I know I'm to assume the Earth is a perfect sphere in this case. Assuming the 103 degrees is measured as latitude, I've calculated the distance in kilometers (Xp in the second equation above) to be 1.1453e4 km. I know I need u = p at the turning point, but not...
Hi,
Just have a question about the method in attempting this two-stage epicyclic gear-box.
We are given the following information about the number of teeth: S1 = 48, P1 = 28, S2 = 96, and P2 = 48
My attempt:
1. Work out the number of teeth for the two ring/annulus gears
From geometry, we can...
I was trying to research about polarizing lasers for an experiment, and there were some things that were confusing? A website said,
I was wondering if the polarization ratio was the same as the extinction ratio?
Also, I was curious because I thought 100:1 would be a lot, and not much light...
The solution can be found at https://study.com/academy/answer/an-insulated-rigi...
After using the two equations I can't see
why (h2-h1)/(u2) should equal (T2)/(T1).
Can someone explain why specific heat ratio is equal to temperature ratio?
Hello! Is there any simple (i.e. using some physics arguments, without actually doing the math) explanation for why $$\sigma(pp \to \pi^+d)/\sigma(np\to\pi^0d)=2$$ where d is the deuteron? Thank you!
Honestly no idea how to get an answer. I found the electric field between the planes and out of it in those two cases but this didn't take me very far.
The final answer is E(B)/E(A)=2. Can someone please explain why?
When does an on/off ratio become impractical? I've read that typical CMOS devices have an on/off ratio of 10^6-10^10. Is there a lower limit that prevents logic devices from functioning appropriately? As in, what is a practical lower limit for the on/off ratio but still enable logic functionality?
Hi everybody,
Poisson's ratio determine that when applying force in one direction (let say z direction) it would cause a relative major strain at that direction, and also two additional strains at the two other directions (x & y).
My question is, what is the explanation for the change in the...
I found that ρn = √(2n+1)/(n+1).
Then, I found ρ = lim when n→∞ |(1/n) (√(2n+1))/((1/n) (n+1))| = 0
Based on this result I concluded the series converges; however, the book answer says it diverges. What am I doing wrong?
There's a micro motor with a gear ratio of 298:1 and there's a servo with a ratio of 188:1.
The first runs at 12v and the other at 7.4v.
How is it that the motor with the bigger gear ratio has only a 70 oz-in torque, while the second motor has a 560 oz-in torque?
First motor ...
I do not know where to start. I draw scalene triangle and assign each coordinates to the vertices. Tried writing something but none working. Please give me a hint to start.
Thanks
Im having a really tough time with this problem, I am assuming that in order for q'(z) to be a maximum, e^(-az/L)sin (pi(z)/L) must be a maximum. I believe this occurs when the derivative with respect to with respect to z/L is zero, which gives me z = 0.322L, but I am not sure if this is correct...
Determine Convergence or divergence and test used
$\displaystyle\sum_{n=1}^{\infty} \dfrac{1+4^n}{1+3^n}$
W|A says diverges using ratio test so
$\therefore L=\lim_{n \to \infty}\left|\dfrac{a_n+1}{a_n}\right|>1$
Steps
$\displaystyle L=\lim_{n \to \infty}\left|...