In mathematics, a negative number represents an opposite. In the real number system, a negative number is a number that is less than zero. Negative numbers are often used to represent the magnitude of a loss or deficiency. A debt that is owed may be thought of as a negative asset, a decrease in some quantity may be thought of as a negative increase. If a quantity, such as the charge on an electron, may have either of two opposite senses, then one may choose to distinguish between those senses—perhaps arbitrarily—as positive and negative. Negative numbers are used to describe values on a scale that goes below zero, such as the Celsius and Fahrenheit scales for temperature. The laws of arithmetic for negative numbers ensure that the common-sense idea of an opposite is reflected in arithmetic. For example, −(−3) = 3 because the opposite of an opposite is the original value.
Negative numbers are usually written with a minus sign in front. For example, −3 represents a negative quantity with a magnitude of three, and is pronounced "minus three" or "negative three". To help tell the difference between a subtraction operation and a negative number, occasionally the negative sign is placed slightly higher than the minus sign (as a superscript). Conversely, a number that is greater than zero is called positive; zero is usually (but not always) thought of as neither positive nor negative. The positivity of a number may be emphasized by placing a plus sign before it, e.g. +3. In general, the negativity or positivity of a number is referred to as its sign.
Every real number other than zero is either positive or negative. The non-negative whole numbers are referred to as natural numbers (i.e., 0, 1, 2, 3...), while the positive and negative whole numbers (together with zero) are referred to as integers. (Some definitions of the natural numbers exclude zero.)
In bookkeeping, amounts owed are often represented by red numbers, or a number in parentheses, as an alternative notation to represent negative numbers.
Negative numbers appeared for the first time in history in the Nine Chapters on the Mathematical Art, which in its present form dates from the period of the Chinese Han Dynasty (202 BC – AD 220), but may well contain much older material. Liu Hui (c. 3rd century) established rules for adding and subtracting negative numbers. By the 7th century, Indian mathematicians such as Brahmagupta were describing the use of negative numbers. Islamic mathematicians further developed the rules of subtracting and multiplying negative numbers and solved problems with negative coefficients. Prior to the concept of negative numbers, mathematicians such as Diophantus considered negative solutions to problems "false" and equations requiring negative solutions were described as absurd. Western mathematicians like Leibniz (1646–1716) held that negative numbers were invalid, but still used them in calculations.
$$W = - \int _ { a } ^ { b } \vec { F } \cdot d \vec { r }$$
( The Force here is referring to the applied force, When moving a positive charge towards another positive charge(stationary) / field
In this formula why there is a negative sign in the formula? I am not asking the sign of the total...
I have to find resultant for this couples:
My sir resolved given forces into components like this:
He considered Fx couples for sides 3,4,5 triangles:
He wrote resultant force for this above diagram: ##\Sigma F_x = \textbf{-}2*\frac{4F}{5}##
we know that if the applied force is in the direction of the displacement then work done is positive.But in case of bringing 2 opposite charges from infinite to a certain distance,the work done is negative even the force and the displacement of the charge is in the same direction.
From...
Equations:
Question:
Using the equation for t' I got the answer -0.00000499756s (Wrong anyway)
As we know the values:
v = 0.67c m/s
x = 3900 m
t = 0.000005 s
Also how can time be negative? Does this mean that event 2 happened before the first event when t = 0?
In Mathematical Methods in the Physical Sciences by Mary Boas, the author defines the Laplace transform as...
$${L(f)=}\int_0^\infty{f(t)}e^{-pt}{dt=F(p)}$$
The author then states that "...since we integrate from 0 to ##\infty##, ##{L(f)}## is the same no matter how ##{f(t)}## is defined for...
We express such equations by $$\frac{dx}{dt} = \beta - \gamma \cdot x$$, t denotes the time.
In this case, γ depends on x, thus the dynamic equation should probably be:
$$\frac{dx}{dt} = \beta - \gamma(x) \cdot x$$
1. Setting the equation to 0 leads to two different cases:
If x < K: xST = γlow...
Negative Hydrogen Ions in Cyclotrons and elsewhere
I was vaguely aware that negative hydrogen ions are used in some cyclotrons and this improves beam current.
I've been thinking about this recently after noting that hydrogen is actually quite electronegative in comparison to most metals (just...
From my understanding, the root locus is only concerned with open loop gain. I figured this means you would ignore the negative feedback loop and calculate the root locus from just the plant's function
Workings:
zeros: -1
poles: 0, -2, -2,
relative degree = 2
=> 90-degree asymptotes
meeting...
How can a negative charge move towards a position of a higher electric potential from lower potential but lose electric potential energy?From my understanding, I understand that for a positive charge, it must lose potential energy from the electric field as work is done by the electric force in...
What does it mean for an orbit to have a negative inclination? is it equivalent to an orbit with the same positive inclination but a shift in the node \Omega by \pi ?
Hi all,
I’m having some trouble finding a minus sign in a standard calculation I have been doing. I am trying to show that if there is no enclosed current around the example loop in the enclosed jpeg, the four piecewise paths add up to zero (for the line integral part of Amp’s law). For this...
I have a question on what happens to MOS capacitance Cgs+Cgd, when Vgs goes negative in the NMOS shown. I see that when Vgs goes negative, the channel is full of holes because of p- substrate, which means we see the Cox capacitance (without any other capacitance in series), but I am not sure if...
Homework Statement
-2^x = y
Homework EquationsThe Attempt at a Solution
When I plug this function in my graphing calculator, it appears to be 2^x reflected across the x axis.
This doesn't make sense to me. For example, for x values of 1 and 2, the value of y is not on the same half of the...
Homework Statement
I have a material placed between parallel plates depleted of free electrons and contain negative ions. What would happen to the charge stored across the plates? Would it still be similar to placing a capacitor with a di-electric constant between them?
Homework Equations
Q=CV...
Its stated that empty universe should have a hyperbolic geometry (Milne Universe) but I don't understand how its possible.
$$H^2=\frac {8\pi G\epsilon} {3c^2}-\frac {\kappa c^2} {R^2a^2(t)}$$For an empty universe when we set ##\epsilon=0## we get
$$H^2=\frac {-\kappa c^2} {a^2(t)}$$...
How could we detect negative mass matter? The only proposal I've ever heard of is that we could detect there's a cutoff frequency in the gravitational waves we receive, due to attenuation of those lower frequency waves by negative matter. Are there more experiments that could be conducted...
Excuse me for bad wording in the title, but there is only so much you can do with the character limit.
So, has there ever been a proposal for a mechanism through which negative energy density could be created? Or the only possibility considered so far was that it would have been created in the...
what are the negative effect of hystersis in metals
or negative effects of magnetic hystersis
for electrical hystersi
over heatin in wires causing low energy transfer and effency
Homework Statement
I am revising on the derivation of the differential equation of energy (White's Fluid Mechanics 7th ed) and I'm having trouble understanding the sign convention used in the viscous work term.
The textbook first define an elemental control volume and list out the inlet...
Homework Statement
A line makes some angle T with each of x and z axis, and angle U with y-axis so that sin^2(U)=3sin^2(T).
Homework Equations
2cos^2(T)+cos^2(U)=1 ...(i)
cos^2(x)+sin^2(x)=1
The Attempt at a Solution
Using the above two eqns. give us the correct value for cos^2(T) which is 3/5...
Hey,
I'm designing an HVAC system for a laundry building. I have vacuum equipment (Vacuum press and Vacuum Ironing boards ) in the space which have a vacuum outlet the is taken outside the building through individual ducts. When all machines are operational, 877 l/s of hot air and moisture would...
Homework Statement
Find ##R_4## for ##g(x)=cos(πx)## on ##[0,1]##
Homework EquationsThe Attempt at a Solution
(i) Since we want ##n=4## even sub intervals between ##x=0## and ##x=1##,
intervals are ##[0, \frac{π}{4}]##, ##[\frac{π}{4}, \frac{π}{2}]##, ##[\frac{π}{2}, \frac{3π}{4}]##...
Yesterday I wrote a simple computer simulation for a spring which, when released, sends two masses flying in opposite directions, and views the event from two different reference frames. My goal was just to convince myself that relativistic mechanics is self-consistent and indeed every time I...
Homework Statement
prove (5-n^2)/(3n+1) diverges to negative infinity as n approaches infinity
Homework Equations
For all M>0 there exists an N in the natural numbers such that for all n >= N, x_n <= -M
The Attempt at a Solution
Let M be an element of the field of the real numbers. Let N in...
Homework Statement
The question askes about the path of the electron. I need to know if I am doing it correctly whether it was asked for a proton or an electron.
Homework Equations
F=QV⊥Bsinθ
The Attempt at a Solution
I answered it C. Because it is an electron, I used my left hand. My thumb...
Homework Statement
If x1 and x2 are the initial and the final position vectors of particle respectively. Then, displacement of the particle is delta x = x2 - x1
But my question is how to know that the displacement is negtivive and its direaction? (could you provide a practical example so that I...
Question:
A distance R is measured to be 3.400 ± 0.007m. What is the absolute uncertainty in R^−2?
Attempted solution:
Relative uncertainty: 2* (0.007/3.4) = 4.11E-3;
R^-2 = 3.4^-2 = 0.0865 m^-2;
Absolute uncertainty = R^-2 * relative = 0.0865 * 4.11E-3 = 3E-4 m^-2;
Any help would be greatly...
If we split H2S we get
H2S = 2H+ + S2-
Where does the negative charge come from in H2S? Do we get 2- charge from the 2H atoms (now two protons after losing the electrons), I mean 2H+ or 2 protons get separated leaving behind the two electrons on S?
In a coordinate bond, why H^+ atom don't get the negative charge? as an example [NH4]^+
If we split [NH4]^+, we get NH3 + H^+. In NH3, N and 3H atoms have completed their octet and H^+ accepts the lone pair of electrons from the N, As we know H^+ has no any electrons but a proton. If it receives...
Homework Statement
So this is a problem I've been facing while finding the area under some curves, for example finding the area bounded by sinx and cosx between pi/4 and 5pi/4. integrating sinx-cosx with these limits would result in the positive and negative areas cancelling out, how do I get...
So, velocity is a vector, right?
And vectors can't have negative magnitudes, right?
Then why is leftward velocity considered negative in 1D kinematics? It just seems off to me.
Same with acceleration, and pretty much _every vector in all of physics._
I'm going over applications of logarithms in my College Algebra class and I'm at a part where it talks about pH scales, and it shows the pH concentration of a substance to be the negative logarithm of hydronium ions.
I want to know why the logarithm is negative, so I googled it and the answers...
Allegedly, string theory (in it's simplest form) predicts that cosmological constant must be negative (or zero). Can someone explain where does this result come from? A reference would also be welcome.
I'm trying to find ##\sin (\arccos x)##. I let ##\theta = \arccos x## and then use ##\sin ^2 \theta + \cos ^2 \theta = 1##, I get ##\sin (\arccos x) = \pm \sqrt{1 - x^2}##. I'm not sure whether to take the positive or negative root. On Wolfram Alpha is shows that the result is the positive root...
The following from Wiki re Hawking Radiation:“... vacuum fluctuations cause a particle–antiparticle pair to appear close to the event horizon of a black hole. One of the pair falls into the black hole while the other escapes. In order to preserve total energy, the particle that fell into the...
Homework Statement
Homework EquationsThe Attempt at a Solution
Was wonder how the isotherm is negative? Is it because it is going counterclockwise (the arrows)? If this is the case, i don't see why a-c would be positive work...
I'm just confused on whether work should be positive or...
Homework Statement
I am conducting an experiment where I am interested in finding the absorption coefficient of different materials as muons pass through them. My data was all well until I realized more muons were measured AFTER they passed through one of the materials, which makes no sense...
I'm currently developing a heat sink for a product that produces up to 150 W max power dissipation. I'm currently getting a negative thermal resistance for the heat sink. I don't think that is possible..
I'm not sure how to move on at this point to properly design a heat sink to meet the heat...
In refraction of spherical surfaces, We derived the formula to be:
## u_2 L^{'} = u_1 L + (u_2 - u_1) R##
Where ##L^{'}## is the reciprocal of the distance of the image.
##L## is the reciprocal of the distance of the object.
##u_2## is the refractive index of the medium that the light ray is...
Homework Statement
Homework EquationsThe Attempt at a Solution
I thought it would become d/dx(-kAc*dT/dx)+hp(T-T)=0 instead of where the equation in the red box? I don't see how are they equivalent [/B]
If an electron starts from rest 85.0 cm from a negative fixed source charge of -0.135 micro coulombs we use the equation ke final - ke intial + pe final - pe intial. In solving you use ke = pe which appears to cancel out the inital kinetic and potential energy but how can the initial potential...
Homework Statement
Hi,
Here is what I know about the Ideal Op-Amp.
- The open loop voltage gain is infinite
- The output voltage is given by the following $$v_o = A(v_+ - v_-)$$
- Only with a negative feedback loop is $$ v_+ = v_-$$
My query is with regards to the negative feedback loop...
Hi,
I recently tried to create diffraction gratings using the negative film of a disposable camera. I designed them so the 'slits' were black and the rest was white so on the negative film the slits would be transparent and the rest would be opaque. It didn't work however. Does anybody have any...
Homework Statement
I'm trying to compute the square amplitude ## |\mathcal{M}|^2 ## for a decay process in which a Majorana fermion, call it ## \chi_2 ##, decays into another Majorana fermion, ## \chi_1 ##, and a vector boson denoted by ## A^{\mu} ##. The model is such that the mass of the two...