Classical Physics

Hi everyone Im new here...but love all the discussions going on.....I have a question for my uni assignment, that has totally stumped me....and ive never been very good at physics... So if anyone could shed any light it would be massively appreciated! Question: The arrow fired as described in part (a) reaches a maximum height of 125 m above the ground before starting to fall back downwards. When the arrow hits the ground, the archer notices the head penetrates 20.0 cm into the earth. By considering the energies involved, calculate the speed of the arrow when it hits the ground and then its deceleration as it penetrates the earth. Quote your answer to three sign…

At the end of the month, most of us wonder- why? The electric bill! Why so high? A major portion of the income we draw from our earnings is spent in paying the ‘bills’ and the heftiest one of them is the ‘electricity bill’. tell me is it not better if we just learn how to make solar panel at home? Search what you need here: http://www.howtomakesolarpanel.biz/

I'm working on constructing a wind turbine for a project. I have a Treadmill motor with a Flywheel and a spot for a pulley on the shaft of the motor, the spot for the pulley is 1.3 inchs diameter I have The other end of the pulley which is 4 inch diameter and have the blades on this part. (I did this to step it up to increase speed to motor) now I'm concerned that the wind will have trouble making this setup work because of the weight the flywheel has should I remove the flywheel or keep it? thank you for your assistance.

Which of these that follow would you think are confusing to a person learning the basics ? The first 8 expressions are meant to convey the same information . 1 , Y = Sin x 2 , Y = sin x 3 , Y = sinx 4 , Y = Sinx 5 , Y = Sin (x) 6 , Y = sin (x) 7 , Y = Sinex 8 , Y = sinex 9 , Y = 0.000000700000131

I'm not sure if anyone has an answer but is there an infinite amount of points an object could be in between two objects? Or is there at some very small level a finite amount of points an object could be at between two points? I am thinking about in existance, not just in a theoretical two points like in math. What I'm thinking is that between points A and B, as an object moves between them, couldn't you keep breaking up the amount of space it traveled per unit of time? Also, is there finite unit of time, or could that be broken up two into infinitely smaller pieces of time. One way I have tried to think of it is with gravity: Fg = G(M1)(M2)/(r2) If the di…

Hi all I am new to these forums. I came here because I had an idea for generating electricity but needed someone to tell me whether it would be feasible or not. First let me preface my idea by saying that I am aware of the conservation of energy rule. However I wonder if one can use other forces to kind of get around it. Here's the idea. First I build a large plant at the bottom of Mount Everest. The plant runs on electricity and turns a body of water into hydrogen and oxygen by electrolysis. I now dispense with the oxygen and send the hydrogen up the side of Mount Everest. I'm not sure how to get it up there - perhaps fill a blimp and the blimp tow…

Two cars face each other on a horizontal road. Car A starts from rest at t=0 amd travels with a constant acceleration of 6ft/s^2, until it reaches a speed of 80ft/s. Afterwards it maintain the same speed.Also after t=50 sec , Car B located 6000 ft down the road is traveling towards A with a constant speed of 60 ft/s. Determine the distance traveled by A when they pass each other. ------------------------------------------------------------------------------------ I was told that for car B we use (t-50) and for car A (t). My work so far : S(A) = 0.5(6)(t^2) +0 +0 S(B) = 6000 + (-60)(t-50) + 0 Set S(A)=S(B) I get two values for t , one is acce…

Can we confirm, that: [math]\vec{F}_{12} = - \vec{F}_{21}[/math] [math]\frac{d \vec{p}_1}{dt} = - \frac{d \vec{p}_2}{dt}[/math] so that, integrated over time, w.h.t.: [math]\delta \vec{p}_1 = - \delta \vec{p}_2[/math] and so ensuring, that total momentum p1 + p2 stays the same?

Hello everyone, I am using Mdynmix program in doing molecular dynamics simulation. Now I have a problem of obtaining the radial distribution function. Maybe there are some of you who have used this software, I really need some help on this. Cheers, Bryk

Ok I had Thin coated wire wrapped around a insulator about 200 times wound and connects the wire leads to 16 volts AC adapter I was holding a Magnet (small neodymium kind). when i held it near it I got zapped the magnet wasn't touching the current at all it was about 2 inches away from it, I'm Very curious as how this happened. my current theory is that the electromagnetic feild (with the 16 volts) traveled to the magnet and to my hand. can any one help explain what just happened

Scientists acknowledge some of the gaps in our understanding of the world or cosmos. For example, the relative rarity of lightning out on the high seas: http://www.science-frontiers.com/sf019/sf019p10.htm Who would like to kick that one around? Many texts admit uncertainty about how lightning really comes about. How about that one? Even when the consensus is but a shrug and a funny face, whatever we come up with will be called pseudoscience because the approved solution is to have no idea. Hopefully, those of us who are retired are relatively free to ignore the pressure and bounds of organized agendas. Who in the world can force us to play dumb? Trying to think beats …

The problem I have is one of geothermics, specifically...and I considered posting this in the earth science section, but I figured you physicists might be of more assistance with this: I am working on converting thermal conductivity (k) values for various rocks and minerals from W/m*C (Watts meters-1 degrees Celsius-1) to W/m*K (Watts meters-1 degrees Kelvin-1). Here's an example: Source 1 gives kgranite = 2.4 W/m*C Source 2 gives kgranite = 3.0 W/m*K So, acknowledging that 1C = 274.15K, dividing 2.4/274.15, canceling C for K...the answer 0.00875 W/m*K is of course nowhere NEAR 3.0 W/m*K. Am I doing something wrong? Or has one of these sources mislabele…

Whereby hot fusion in stars does not lead to explosive regeneration, it would seem that it must not be self-sustaining and therefore must depend upon a companion source of heat. Can anybody help me to get that notion out of my head?

How can it be that the electric field is [math]c[/math] times greater than the magnetic field while their energy densities are the same?

I've been doing a little research on the earth batteries of the 1800's. Very interesting. I managed to light a single LED light with a series of 8 cells consisting of sand, plastic cups, a graphite rod, and some alloy metal (I'm not sure of the exact composition). I set it up similar to an old wet cell; graphite to the alloy metal immersed in the sand which was in a plastic cup, making a total of 8 cells. The total reading on my multimeter was areound 6-8 volts, it didn't exactly remain constant. The LED did not shine brightly either, nonetheless light was still being emitted. When I tested the voltage entereing the LED though it was only around 3-4 volts. The current wa…

solar power can be made an option to prevent this world from the upcoming energy crisis. not only this but it also helps to conserve ecology in other way.

Hello What is the relation between the resistance and lost Thermal energy in a circuit ? I mean >> If we put a ((big)) resistance .. the Intensity of the current will lessen If we are trying to lessen the lost energy (it is lost as heat) >> what should we do ?? use a material that has low Resistivity ? or high Resistivity ?? the first will make the intensity of the current increase >> and that it self affects the lost energy as heat and related to this in "coldeg's X-ray tube" why do we use copper (attached to the target of the Wolfram) ?? Thanks

If I am correct, electric current is an entropic process comparable to heat-disequilibrium where it is charge instead of temperature that is moving toward equilibrium. Voltage, I thought, refers to the strength of the current due to the level of charge disequilibrium between the electrodes. Temperature, I think, is a measure of average kinetic energy among the particles of a system or part of a system. So I think that temperature would be more like charge and voltage would be analogous to what? Is there a term for rate of heat transfer? Can it be negative except in the sense of the direction changing?

Can Negative DC voltage be measured? If yes then how and what will be the range of its values.

The equation of motion for a pendulum is y''=-(g/L)sin(y), where y represents the angle of the stiff rod with respect to the vertical, g is the acceleration of gravity, L is the length of the rod. y also varies with respect to time. I've seen how this particular equation is derived, but I would like to know more about the general problem of modeling mechanical systems with constraints. Does anyone have some insight to offer? How could I view this problem from the mechanical perspective (finding positions, energies, momentums, etc.).

How do you EMP harden a computer

I don't know much about them except what i learned from power labs but i know they use electromagnets to accelerate a projectile. and that because there is no "burn rate" in theory the projectile should be able to reach the speed of light. but as in any experiential technology there must be a problem that is preventing it from being perfected so what is this problem and what are some ways that this could be solved in the future

if opposites forces attract, it seems to me that the magnetic force in a bar magnet would have an "0" shape near the center of the magnet, But what we see is more like a figure 8. Why don't thes forces attract each other? And what's going on in the middle of the magnet? are the positive and negative energies canceling each other out? It seems like magnetic force would burn out pretty quick if this is the case.

Hello I want to ask.. When there is a circuit ( battery - Rheostat -lamb) When we decrease the Rheostat .. the current will increase But momently there will be a self induced current which will weaken the current I want to know >> momently , which one will beat the other ?? And why ? And If we increase the Rheostat , the current will decrease .. but there will be a self induced current which will strengthen it >> which will beat ?? AND why ??

Magnetic bar has two poles , i.e., S and N. Is it impossible to make monopole magnetic bar? If not, why is it impossible?