ok, so, I know e=mc2 is a way i can find what quantity of energy a mass has.
and i know that as objects increase in speed they become more massive, which i assume is also elegantly portrayed in this equation.
but, this kind poses a problem for me, because i am wondering how much velocity...
Homework Statement
Calculate the percentage increase in the mass of an apollo rocket as it escapes from the Earth's gravity at 11.2 kps
Homework Equations
11.2 kps = 11, 200 m/s
E= mc^2
mv= mo/ sqrt (1- v^2/c^2)
mv= mass of the object relative to stationary frame
mo= proper...
Hi for a bit of work I have to explain the advantages and disadvantages of a higher engine intake air temperature.
I have been told that it decreases the power output of the engine but I can't seem to work out why it would decrease.
I also want to comment on how it affects the efficiency but...
Does entropy in a closed system always increase OR remain constant ( in equilibrium ).
I have a friend arguing it is ALWAYS increasing.
His latest argument was, "if no energy enters or leaves an isolated system, the availability of the remaining energy decreases."
Hello all
when atom absorbed a photon , photon changes to virtual photon in atom and mass of atom must increase .
but in other form electron absorbed the photon and pull off atom like photoelectric effect .
My question is in photoelectric effect , mass of metal base increase or decrease and...
Say you compress a closed container full of gas (you reduce its volume). You are not holding the pressure constant or anything.
As you do this, the temperature increases, but why? My best guesses are:
- some of the energy you use for pressing down on the container is transferred to heat...
Homework Statement
find the intervals of increase or decrease of the function f(x)= (3/(x^2+11)-1
i already find the 1st derivative f'(x)= -6x/ (x^2 +11). After that i didnt know how to proceed to find the interval. I need help for the solutions.
I am new to the forums and need help with something. I have been using a spreadsheet that somebody else made in order to help me design an electric motorcycle. I have been inputing my own data using most of his calculations and I have noticed that he did not calculate any aerodynamic parameters...
As the title says, what are some scientifically valid ways to increase your life expectancy? That is, which practices (ex: diet, exercise, etc.) have been shown to increase the average life expectancy in experimental studies?
Hi,
I know potential = mgh where g can be considered constant close to the surface of the Earth. So as we move away from the Earth the h and P increase.
And taking P = 0 @ infinity then P = -GMm/r so P < 0 always and increases to 0 as you move away from the Earth.
So it seems there is no...
Hello,
I'm not sure if this is the right place for this question, but I am trying to understand how placing electrodes in the brain elicits action potentials.
In a neuron (brain cell), there exists a solution of sodium and potassium ions (among other things). When the brain wants to...
Hi,
I've been working on an experiment where I dip LEDs into liquid nitrogen and note the color change. All online sources I've seen predict that the wavelength of the light emitted by the LED will decrease upon immersion.
What I've been observing, however, is a sudden decrease in...
Hello,
I'm not sure if this is the right place for this question, but I am trying to understand how placing electrodes in the brain elicits action potentials.
In a neuron (brain cell), there exists a solution of sodium and potassium ions (among other things). When the brain wants to produce an...
Imagine an electron of mass m_e inside a hollow dielectric sphere.
Assume that the electron is traveling with constant velocity v relative to the sphere.
The momentum of the system p comprises just the momentum of the electron
p = m_e v
There is also a circulating magnetic field B...
In leukaemia since immature white blood cells increase, do they overcrowd and decrease mature white blood cells. So does neutropenia and thrombocytopenia, leucocytopenia occur in leukaemia. Or does this deped on subtypes eg in some leukaemia B lymphocytes increase. Thanks :smile:
Homework Statement
Does anyone understand why density would increase when the poisson ratio is greater than 0.5 as indicated in this slide from my professor:
Does this density increase apply to a system undergoing tension or compression or both?
the pressure of air inside a car tyre increases when the car is traveled at HIGH SPEEDS?why is this so?my guess is that at high speeds,the friction between the tyre and road surface increases..so kinetic energy is dissipated as heat energy due to friction.this heat is transfers to the inside of...
Homework Statement
In which case of mixing of a strong acid and a base each of 1 N concentration, temperature increase is highest.
A)20ml acid-30ml alkali
B)40ml acid-40ml alkali
C)25ml acid-25ml alkali
D)35ml acid-15ml alkali
Homework Equations
Law of Equivalents
The Attempt at a...
I have an impulse of ~200mV, ~50nA for about 0.15 seconds. To interface with my circuit, I need it to be 1V+. The problem is, I don't want to use an opamp, or something else that needs to be constantly powered. An ideal solution would be a relay or a FET that has a gate threshold in the...
Adsorption of Benzene using Activated Carbon - Increase in concentration!?
I'm not quite sure where to post but here it goes.
I'm performing an adsorption experiment of benzene from solution using commercial activated carbon. It is expected that the concentration of benzene would decrease...
This is wonderful news. There has been an upward trend over the past months and looks very good for Obama.
http://www.huffingtonpost.com/2012/10/05/jobs-report-unemployment-rate_n_1942067.html
Hello, I was just reading how the second law of thermodynamic is the only principle of physics that is irreversible, and that fact appears to have a correlation with how we view time and how time can only move in one direction, being the same as the flow of entropy. So, are entropy and time...
If you have a tank of water then the speed of sound is 1482 m/s. If you add ethanol, the speed of sound increases. This seems to be pretty linear with the % concentration of ethanol. why does ethanol (or propanol) increase the speed of sound?
thanks
Homework Statement
Given that P & V increase in direct proportion such that
When P= 1 atm, V= 1L; P=3 atm, V=3L
Describe a possible setup for the pressure to rise as the volume increases.
Homework Equations
F/A=P
V= 2pi.r.h
The Attempt at a Solution
Suppose a system of
1. a...
I read somewhere than whenever we increase the velocity of a particle, the mass of he particle also increases. I also read that it is impossible reach the speed of light as the mass of the particle, just before reaching the speed of light, will become infinite (not infinite but very large) and a...
Hello all,
I'm thinking about the following exercise from Intro to stoch. analysis:
Let V be a continuous, nondecreasing function on \mathbb{R} and \Lambda its Lebesgue-Stieltjes measure. Say t is a point of strict increase for V if V(s) < V(t) < V(u) for all s<t and all u>t. Let I be the...
Would a bullet have longer trajectory,because the air helps it ''glide''?Does this mean that if you fire the same gun and bullet in vacuum and in the air the one fired in the vacuum will fall to the ground a lot more quickly?
Trying to understand what will happen to the fluid in the following scenario.
Lets say there is a length of pipe with an OD of 4", what would happen if halfway along the pipe the pipe OD increased to 6" (gradual increase).
I believe the pressure of the fluid will decrease, would the flow...
After watching a few rowing competitions of London Olympics 2012, a question came to my mind.
In the competitions rowers (Not sure if this is the word used for athletes) synchronize their
rowing strokes. All 8 athletes' oars touch and leave water at the same time. This causes the boat to...
How to increase the current?!
I'm designing a drive circuit for a 12V DC motor
I'm using a (2N3055 BJT) as a switch to control the output, and I'm using a (74121 monostable oneshot) to control the BJT switch.
So, the output of the 74121 is fed into the base of the BJT.
Here is the...
So my friend came home from work and asked me why adding vinegar to water aids in evaporatoin. He said they had them clean with this solution because it helped the water dry up faster. However, I've only had two years of study in chemistry and I can't say I know for certain.
I know that...
First of all - I'm new here, and this forum looks awesome!
As for my post, I'm going to be using an inductor to emit an electromagnetic field, and was wondering if you could somehow either increase it or isolate the emission maybe via antenna? I know antennas are typically used to convert...
With CERN's Large Hadron Collider being in the news recently, I began to think of a question that bothered me for years about particle accelerators.
It is well known in physics that mass increases as velocity does (Special Relativity if I'm not mistaken), so if these particles in the LHC are...
So far whatever I've read on competance (both natural and artificial) is that it involves the uptake of DNA. Does this mean that as a result of competance the genome's length increases each time DNA is taken up?
If I understand correctly, an object with mass can't reach the speed of light because at the speed of light it would have infinite mass (and presumably fill the infinite universe). But what happens as an object approaches the speed of light? Eg., if an object traveled at 1% of the speed of...
Hello, I want to build an electrical circuit powered by a temperature diffence between two unlike couple, such as copper and iron. I know a good thermocouple would be better, but I don't think I'll be able to get a hold of those materials as easily.
My current plan is to use a solar oven to...
Hi All,
Protons repel each other and in order to make them collide in the LHC huge amounts of energy have to be put in place, my question is; if we launch a beam of electrons transversal to the beam of protons and right in the collision point of the protons, would not this increase the energy...
Hello all, long time follower, first time poster.
(Also feel free to move this if it's not in the right section.)
Basically I have this mechanism pictured here:
You can imagine that the drawing is of a top view of a section cut of the total mechanism. This is the radius view, the full diameter...
Forgive me, for i do not have any degrees in physics.:shy:
If 1 large object like a planet were to orbit near another large planet/moon.
It would in theory be possible for both objects to increase their speed of rotation, as long as they end up rotating in opposite directions right? Of course...
Guys I'm weak in heat and kinetic theory, so I'm going to need extra guide and pointers from you guys to solve this and the coming questions. Thank you.
Question:
A pond of water at 0 degrees Celsius is freezing. The thickness of the ice layer is h and the top surface of the ice remains at a...
Homework Statement
very 'uninformed' person here please bear with me. this relates to a piece of work equipment that i use but am not comfortable doing so.
a 6" aluminum rod that weighs 6# is extended from its vertical away from the body to reach a 'target' from 4' to 6' away. the rod will...
Hello Everyone,
I have been asked to find out what it takes to bring 775 gallons of water at 70 deg (room temperature) to a rolling boil (approx 212 deg) via 25psig steam.
I have 68 square feet of heat transfer surface (stainless steel tank) with no agitation.
I haven't been successful...
Increase in voltage = decrease in current??
Homework Statement
Electric power is transferred over large distances at very high voltages. Explain how the high voltage reduces power losses in the transmission lines.
Homework Equations
V = IR
P = VI
The Attempt at a Solution
From...
Homework Statement
To what value would you have to raise the temperature of a copper wire (originally at 20 deg/C ) to increase its resistance by 14 % ?The Attempt at a Solution
temp. coeffic of copper = 0.004
delta T = 0.14/0.004
delta T = 35 deg/C
why is this incorrect.
Hello,
I was wondering if anyone know the physical explanation about the following:
What happens if I combine two Identical LEDs with the exact same spectral profile (eg 350-450nm with 400nm center wavelength and peak).
Assuming the total power of each LED in watts is 300mW. Will...
Homework Statement
By what factor does the total partition function (excluding electronic) increase when 20 m^3 of Neon at 1.00 atm and 300 K is allowed to expand by 0.0010%?
Homework Equations
translational partition function qt= (V×[(2∏mkT)]^3/2])/ (h^3), vibrational partitition...
First my notes discover that for an isothermal transformation;
ΔW ≥ ΔF
Where W is the work done and F is the Helmholtz Free Energy, F = E - TS.
Then it defines the Gibbs free Energy;
G = F + PV
"For a system at constant temperature and pressure, G never increases";
So ΔG = ΔF...