Constant Definition and 1000 Threads

Homework Statement my spring constant is 85 N/cm and I have to convert to N/m Homework Equations why does stoichiometry not work on this? How would I approach conversions like this? The Attempt at a Solution I tried converting the 85 N/cm to N/m and ended up getting 85*10^2 N/m. This was...

Hi, Could I please get some guidance on my approach and solution, for this particular problem. Any assistance welcome. 1. Homework Statement An ideal gas is compressed at a constant pressure of 1.3 atm from a volume of 20 L to 12 L. During this process it gives off 3.69 kJ of heat. What is...

In my springs what would the spring constant need to be If I am 1.8m tall and I weigh 68 kg

When we measure the cosmological constant Λ what we are really doing is measuring the longterm value of the Hubble rate, namely H∞, the distance expansion rate that the present rate H(t) is seen to be declining towards and leveling out at. It's convenient to write distance expansion rates as...

When does the value of the "Equilibrium Constant (K)" equal one ? and what does that mean ?

In my textbook it says an isothermal process occurs when the temperature is constant. It also said taht typically, Q,W, and delta U are not 0 in these processes. My question is how can heat not be 0 if temperature is constant? Q=mcDeltaT so if Delta T is 0, then Q also has to be 0 right?

Homework Statement I need to explain for a lab, why the efficiency of a rubber band slingshot constant for different stretch lengths. I don't need math, just a general explanation of why kinetic energy of projectile/elastic potential energy in rubber band is constant. Homework EquationsThe...

Homework Statement A block of mass 1 kg is attached to a spring. The spring extends by 10 cm. Find spring constant.Homework EquationsThe Attempt at a Solution Potential energy of spring = kx2/2 work done by block = PE Hence mg*x=kx2/2 ∴1*9.8*0.1=k*0.1*0.1/2 ∴k=196N/m But solution says mg = kx...

Piran et al., "Cosmic explosions, life in the Universe and the Cosmological Constant," http://arxiv.org/abs/1508.01034 I thought this was interesting. If I'm understanding correctly, the idea is that satellite galaxies such as the Magellanic Clouds have low metallicity, which causes them to...

Homework Statement Choose two masses and vary their separation, measuring the force between them each time. Plot a straight line graph and use the gradient to estimate the universal gravitational constant. Include uncertainties in the results and express values with the appropriate number of...

Homework Statement Not sure if this belongs in the 'Advanced' section so apologies if it does not. I am using a monochromator to measure spectrum lines from a rubidium lamp. From the data (wavelength of spectral lines plus transition number 'n') I am asked to use a graphical method to...

Homework Statement A parallel plate capacitor has a capacitance of 1.5µF with air between the plates. The capacitor is connected a 12V battery and charged. The battery is then removed. When a dielectric is placed between the plates, a potential difference of 5.0V is measured across the plates...

Homework Statement A parallel plate capacitor has a capacitance of 1.5µF with air between the plates. The capacitor is connected a 12V battery and charged. The battery is then removed. When a dielectric is placed between the plates, a potential difference of 5.0V is measured across the plates...

Homework Statement A sample consisting of one mole of a diatomic perfect gas is heated from 25 °C to 200 °C at constant volume. Calculate q, w, ΔU and ΔH for the process, given that Cv = 23.02 J K-1 mol-1 . Homework Equations Im studying for mid terms and i have no lecture notes on diatomic...

Big masses like planets and stars have gravitational fields. Gravitational fields curve space around them. So in theory a particle having mass moving at fixed speed, from its own perspective, will accelerate when moving closer to such a planet. It'll be moving at fixed speed in a curved space...

Generally in chemistry and physics, we learned that a material has a heat capacity at constant pressure. However, I am confused at whether this refers to a constant external pressure or a constant system internal pressure? Thanks.

For time independent Schrodinger's equation in 3-D Where Enx,ny,nz=(nx/Lx2+ny/Ly2+nz/Lz2)(π2ħ2/2m and Ψnx,ny,nz=Asin(nxπx/Lx)sin(nyπy/Ly)sin(nzπz/Lz) How do I normalize A to get (2/L)^3/2? I don't think I understand how to normalize constants.

Homework Statement A ball of mass m rolls down a 3.0 m ramp inclined at 30° above the horizontal, rolls along a flat, friction less surface, and collides elastically with another ball of mass 2m, initially at rest. The second mass then moves along the surface and collides with a horizontally...

Excuse me, If I want to calculate one equation in SI units. Which value of Boltzmann constant I should deal with. Also, the electron temperature it can be used in Kev or it should be in ev. Also, the nm must be converted to meter or it can be used in nanometer.

Could anyone please recommend a paper that accurately gives the value of the cosmological constant? Or else may you reply with values of the cosmological constant that you would you use in your research? Any help would be very much appreciated.

Ok, so here's the deal. I'm working on something that I SHOULD know the equations for after 5 years of school and a degree in mechanical engineering, but then again I can't remember why I walked into a room most times. So if ya'll could give me some guidance and at least a starting point I...

Is the amount of dark energy in the universe constant or else does it increase as the universe expands? In other words is the "anti- gravitational force" that is believed to be caused by dark energy and results in a accelerating universal expansion, a constant value or will it increase as the...

So I have a diff eq dy/dx = ky - w where K and W are constant's I want to draw a phase portrait so i set ky - w = 0 and determine the expression equals 0 at y = w/k so I want to study the behavior of the solution greater w/k and less than w/k so I plug (2w/k) and (-2w/k) and check the...

I know the phase constant depends upon the choice of the instant t=0. Is it compulsory that the phase constant must be between [0,2π] ? I know that after 2π the motion will repeat itself so it will not really matter, but what is the conventional way to write the phase constant in the general...

In an experiment I hope to carry out, one of my "constants" are velocity (constant velocity). I must say a way I will keep this value constant. For example I can not say "I will try my best to pull mass at a constant velocity" "I will take a video of the experiment. When I examine the video, I...

Homework Statement The speed v of sound in a gas depends on the density p and pressure P of the gass. If this dependence is in the form of a power law that is, v = kpaPb where k, a and b are constants (k a dimensionless one). a. Determine by dimensional analysis the values of a and b. b...

One condition for wave interference is that the sources of the waves must be coherent, which means they emit identical waves with a constant phase difference. I can understand that identical waves means they have the same wavelength. However, I don't understand what is a constant phase...

Homework Statement Why for a given constant force, in a study reference system, which point of application moves from A to B, the work of the force is conservative? Homework EquationsThe Attempt at a Solution The only thing I know is that if the angle ##(\vec{F},\vec{AB})## is acute...

Homework Statement A car with a mass of 1,500 kg sits on a suspension system that has four springs. When the mass of the car was originally placed on the springs, they compressed by 10 cm. What is the spring constant for each spring? Homework Equations k = F/x or k = mg/x The Attempt at a...

Homework Statement Consider the nonlinear (ordinary) differential equation u' = u(1-u). a) Show that u_1 (x) = e^x/(1+e^x) and u_2(x) = 1 are solutions. b) Show that u_1+u_2 is not a solution. c) For which values of c is cu_1 a solution? How about cu_2 ? Homework Equations N/a The Attempt at...

I'm starting to question my sanity. This wikipedia article claims a ship with a constant acceleration of 1g will cross 100000 light-years in 24 years by traveller's clock: https://en.wikipedia.org/wiki/Space_travel_using_constant_acceleration Numerous calculators over the web give you the same...

How come that, in the context of discussing the search for gravitational waves, I never see the cosmological constant mentioned ? We know that ##\Lambda \neq 0##, so this seems strange to me; in the presence of a non-vanishing constant, the background is not Ricci flat in the vacuum case, so...

Since Edwin Hubble proposed distant galaxies move apart from each other as spectra of each galaxy is shifted towards the red end. this created the law that universe is expanding exponentially since big bang. and these galaxies spectra are due to stretching of wavelength of light incident from...

I realize that this is probably really basic, but I can't quite conceptualize a hollow metal sphere having constant voltage and zero electric field inside of it. I've searched around on the Internet, and I've seen stuff about Gauss' Law, but even after reading into that a little bit I can't make...

How does one arrive at the following equation to approximate spring constant for solids... using Hooke's Law F ∝-x ⇒ F = -kx and strain∝stress ? k = (m/a2) × (K/ρ)½ where k≡spring constant m ≡ mass of a single atom a ≡ atomic spacing K ≡ bulk modulus ρ ≡ density

Im trying to solve for a constant in an equation and it involves taking the arctanh(6.55) and my calculator is giving me an error, is there a way around this?

Homework Statement It's been a little while since I did one of these. My question is: We have to use http://phet.colorado.edu/sims/mass-spring-lab/mass-spring-lab_en.html to find the measurement of k, the spring factor using two different methods. For the method I am looking at, is the static...

I am doing an Astronomy GCSE. I have to work out the orbital period for a satellite. I have got quite far with it, but I am really stuck. I have spent hours at it! This is the question:- A space laboratory is in circular orbit around the Earth at a distance of 6000km from the Earth's centre; its...

From what I've seen so far, the basis of the solution space for all the constant coefficient homo linear DE's have been linear combinations of the exponential function e or of some polynomial multiplied by the exponential function. Is this always true that these DE's always result in solutions...

Overall I'd say I'm a somewhat secure person; though definitely a bit weaker than average, I'm not an emotional wreck except for when it comes to one thing: doubt of my capacity/potential, which has lately bothered me a lot. Any time of IQ or intellectual superiority are mentioned I go crazy...

So force equals mass times acceleration. What happens then if we pushed a box horizontally without fiction at constant speed? The box keeps moving but acceleration equals zero? Is there still force? Thank you!

the equation for wave velocity is velocity = wavelength * frequency. now by using the Doppler equation for change in frequency and the Doppler equation for change in wavelength. if you multiply those two equations together you get. frequency' *wavelength' = original frequency * original wavelength.

Homework Statement I'm making a program that draws a graph of the weight of an hourglass. Obviously at first we know the weight, and as the grains begin to fall it decreases by the amount of mass in free fall. However I ran into a problem when the grains begin to hit the bottom. It's impossible...

Hi, I am reading the Einstein original paper on Special Relativity, in this link (English translation), I am having difficulties on this sentence: "We have now to show, that every ray of light moves in the moving system with a velocity c (when measured in the moving system), in case, as we have...

Homework Statement . Show that if and, thenis constant in time.Homework EquationsThe Attempt at a Solution

Homework Statement A block of mass "m" is pulled across a rough table by a string at an angle "θ" above the horizontal at a constant velocity. What is an equation for the magnitude of the kinetic friction force, fk? The answer that I was given was μk(mg-T*cos(θ)) Homework Equations Fk=Fn*uk...

Hi, I have the ODE y'''' - 3y' + 2y = 0 The characteristic equation is then $r^4 - 3r + 2 = 0$ So my 1st question, is there some easier way of finding the roots than long division? I looked at the first and last terms to guess the roots (if real) might come from (r-1) , (r+1), (r+2), (r-2)...

Suppose there are two tanks, tank A and tank B, of equal size and both are very large. Suppose the bottom of tank A is at an elevation that is higher than the top of tank B. Suppose there is a very small tube relative to the size of the tanks that connects the bottom of tank A to the bottom of...

Hey! :o I am looking at the following part: The constant field of the differential field $k((x))$ is $k((x^p))$. Hence if $(1)_p$ has a solution in $k((x))$, multiplication by a suitable constant yields a solution in $k[[x]]$. What exactly is a constant field of a field? (Wondering)

Homework Statement A pendulum, initially at equilibrium, is set into motion by a spring-loaded launcher (compressed a distance of 0.0150 m) which fires horizontally. If the mass of the pendulum bob is 0.340 kg and it rises to a maximum height 0.120 m (relative to equilibrium), what is the...