Classical Physics

If an amount of water is added to another amount of water which is 3 times more in volume with temperature 10, what is the temperature of the water, which when added to another, the overall temperature is 20?? specific heat capacity for water = 4200J/kg c below is my solution Let's assume the amount of water is 1 and 3. Say, the energy used to heat up the amount of water of 3 to 10c from 0c is: 3*4200*10 = 42000*3J the energy used to heat up the total amount of water from 0c to 20c is: 4*4200*20 = 84000*4J = 42000*8J Ok, subtract the nergy used to heat up the total amount by the energy used to heat up only the amount of water of 3, and the answer…

Hi again.. I know this can't be that difficult but I am faced with a terrible book and a professor that spends no more than 10 minutes on each chapter. So, here goes.. Again, not looking for an answer, just some ideas on where to start... A 70-kg tightrope walker stands at the midpoint of a 100 m rope. The rope sags 1.5 m. What is it's tension. I know I have to use w=ma to find the weight, and I've tried finding the angle between the 2 segments of rope, but I keep getting goofed up somewhere. Thanks in advance!

I am doing a college investigation and need to find three materials which could be used in the production of a bulletproof fuel tank. i am finding it very hard to find any information. Any help would be much appreciated.

I was doing some calulations for someone showing the point of neutral gravety between two equal sized masses. The vectors from points not between the two masses (I hope that's clear...) all seem to point at the midpoint between the two masses... Is that what happens always? or is it just a conicidence (or misdrawing/calulation on my part)?

Hello, first off, I will warn you that my questions are really fundamentals of Physics that I probably should already know, but EVERYONE doesn't know something until they learn, so here's my chance. First off, I need clarification on some things. I know what an amp is. It's how fast the current is moving. Great. Now Voltage. I know the literal definition. It states that Voltage is the Potenital difference of charges or something ot that effect. What I may or may not understand is it's relationship with Amperage. I know that you can convert high voltage low amperage currents to low voltage high amperage currents, but I don't understand how voltage is measured. It's eas…

Whats the best summery of all basic info that could be found at a liberary.

while reading up on the Hall Effect, i realised that you could set up a distribution of space charge and hold them with the magnetic field, while cutting the wire connecting the metal plate to the external battery(to prevent charge form entering or leaving the plate). hence producing a capacitor. But i realised that if you did so then there would be no drift velocity and hence no force on the charges due to the magnetic field. End result no capacitor.But then brownian motion came to the rescue, untill i realised that the net velocity is 0. any other way? (no heating of the metal plate allowed(work function thing)

Hi all! I'm really stuck on this problem. I have a v vs t graph showing car A at constant acceleration = 0 m/s2 (horizontal line) with a v=8m/s and car B having a constant acceleration of 3m/s2 (found using slope of the line) with average velocity equal to 6m/s (found by (v2-v1)/2). Here's the question: At t=0, both cars are at x=0. Estimate (a) where and when they meet again and (b) their velocities when they meet. 1. I was told that using acceleration I can find x, but I'm thinking I have to do an integral to do this. Is there another way? I was also told this could be solved using a quadratic equation, but I don't understand how. Can anyone give me an idea h…

Would it be possible (in practice) for [math]\phi[/math] in the equation [math]\phi=\int{B\,dA}[/math] to be anything but a whole number?

Our teacher for science requires an "advanced" project for our Enriched class, and some of it might be entered into the provincial science fair. I have absolutely no idea as to what to make. Any ideas on what I can experiment with? This is just like a science fair project. I am 10th grade, and am interested mainly in Chemistry, but Physics & Engineering are good too. As for the difficulty, I was thinking as advanced as possible, more exciting than an vinegar-soda volcano and less lethal than a tesla coil. Sonouminescence, or some other topics of that level which I CAN DO AN EXPERIMENT WITH. And I prefer an experiment in which very few people have died. Thanks a lot…

I got thinking the other day about gravity (dont ask me why, sometimes my mind goes off on tangents). I thought about high school science about how gravity works and realized i never got an explanation that satisfied me. I remember being told gravity is created by the mass of whatever body generates it, the greater the mass the greater the gravity. What i dont understand is how? Is it due to elecro-magnetic fields that they generate, the larger the mass the stronger the magnetic field? Any information you can provide would be appreciated.

sorry if this is in wrong section but..best i could see as topic title says.., how much weight could one normal sized helium balloon lift, the ones you get at the circus/show/party/whatever? or to be more exact, how many would be needed to lift say 100g? thanks in advance.

Hi all, first post - so please be gentle. I am, by far, no expert on all things scientific - so I'd like some help on this query. If, say, you dropped a golf ball and a ten pin bowling ball from the Empire State Building simultaneously, on a calm day, would both hit the ground at the same time? If someone could advise, or post a URL to a definitive answer it would be great!

I was going over the standard block-on-ramp-calculate-the-coefficient-of-friction problem. The coefficient turns out to be tan x, where x is the angle involved. I was just wondering, just what happens to friction when it approaches 90 degrees. Certainly, when in real life when I have a block next to a wall, friction isn't infinite, as otherwise the block wouldn't fall. But then again, there must be some friction, as stick services (like velcro) wouldn't work either.

I'm no physicist but I thought I'd show you something I thought of long ago. Rocket A leaves Earth at .8c to a planet 8ly away. Before it left the astronaut calculated it would take him 6 years his time(approx) to reach the planet if you took time dilation into account. I'm skipping the time dilation math. So when he arrives he calculates his distance travelled to be 6 x .8 = 4.8 ly. What I'm about to say may have already been discussed somewhere else, I don't know. Objects with mass travel a shorter distance between 2 points than a massless photon thru spacetime. In other words mass exhibits a property rarely discussed and that is the ability to cut through spa…

if the government and/or the people of a country paid for a solar panel on their house even something like 2m^2 and a number of batteries to store excess power(like ther would be any) wouldn't they generate a significant amount of power? we could shut down the most polluting powerplants(coal and oil fired) thus saving fossil uels and helping the enviroment. buildings that are larger than the average home could also have additional panels. and obviously people could add more panels if they wanted. any thoughts on this idea?

Here are two questions concerning the circuit things. 1.In a series circuit with a bulb in the middle of it with 5V. (Please neglect resistance of wire) My teacher said that each electronwould lose all of the energy, i.e.5J per second, after they have passed the bulb. So it has a decline in its velocity after passing the bulb? 2.In the circuit above, a voltmeter is connected. The voltmeter starts a new loop for the circuit, so the energy given by each electron to the bulb will change and then how does a voltmeter work? Thanks for any replies.

a projectile near the earth's surface moves in a parabola. so what is the equation for it's path? it opens down, so it is [imath]y=-ax^2+bx+c[/imath], but what are a b and c? if we put one zero at x=0, c goes away. that leaves [imath]y=-ax^2+bx[/imath]. so, what are a and b?

Ok I read on the internet somewere that gravity has the same speed as light does. If this is true how come a black hole can suck light right up? I know this people have done lots of research in order for people to believe what they state, but I believe this is impossible and gravity must have a speed wich is greater than the speed of light in order to suck it up in the matter wich is seen through telescopes. Can someone who knows much about this subject explain how this is possible please. I am barely coming out of highschool and havent studied much but science is an easy subject for me and stuff just makes sense so please tell me how this man is right. Heres a lin…

I hope I'm in the right section. More questions for the astute members of this forum. If a light particle(photon) has no mass then does that affect the famous equation E=mc²? or can a massless photon release energy? If a photon has mass and is absorbed (lost) is there a release of energy equivalent to its mass? If c=0 can there be any energy? or do things have to be in motion for the equation to work?

Hi I readed in many threads in this forum that the speed of light is constant even in a meium like water or glass. That the apparent slowing down is cause by the photons being absorbed by the atoms of the medium and after a moment being re-emitted. The speed of the photon between atom is always c. My question is Why doesn't the light is scattered, dispersed ? How does the atom remember from which direction the photon came ? Thanks For your answers

...My question is if photons are "massless" then why do massive bodies perturb their natural course..? Another question is if light does create a space time flux, which produces gravity....why does the moon still orbit earth in its Umbra?

hi i have a question about antennas (and an unrelated question about gravity) Question 1 does the length of an antenna have to take into account the amplitude? (ive no idea what the amplitude of a standard broadcast radio wave is) if the antenna was smaller than the amplitude, it would not be able to pick up the entire wave, so information would not be recieved, is this right? so if an emp from say a nuke went off, would all electronic devices within range break, or only those with a conductor in the circuit long enough to recieve the full magnitude of the amplitude of the emp? Question 2 anyway, second unrelated question. err after i read http://www.scienc…

Does light have a temperature? Often in photography they discuss color temperature, but does this mean light has a measureable, real temperature? DOES LIGHT ITSELF HAVE A TEMPERATURE?

I'm having some trouble with a couple of the practice problems from a study guide. Can anyone help? 1.)The area of a telescope lens is 4149 mm2. (a) What is the area of the lens in square feet (ft2)? ft2 (b) If it takes a technician 65 s to polish 175 mm2, how long does it take her to polish the entire lens? 2.) The volume of a certain bacterial cell is 1.98 µm3. (a) What is its volume in cubic millimeters (mm3)? mm3 (b) What is the volume of 105 cells in liters (L)? 3.) Convert 709.5 meters to centimeters. Is this right? 7.095 x 10^2 4.) The concept of ____ indicates the ability of a person to measure consistently. precisio…