Physics - June 2007

2007-06-30 08:09:44 · 3 answers · asked by new to this all 1

TRAVEL BACKWARDS THROUGH TIME!!!!!!!!!!!!
Wow, I just came back from yesterday!!!!!!!!!!!!!!!!!!!!!!!!!!!

2007-06-30 07:38:22 · 9 answers · asked by cme2bleve 5

Hey guys, I might be going to a college that is about 1/2 a mile away from an airport. You can literally see the radar rotate from the college steps. I'm concerned about my health because I've heard that radar emits harmful radiation. Is this true? Please offer some educated advice. Thank you!

2007-06-30 07:16:40 · 6 answers · asked by Anonymous

ok I understand how Baird got his first pictures to work using an LDR and have an idea how normal film cameras work. But how do modern electronic / cmos cameras work, please?

2007-06-30 06:56:36 · 4 answers · asked by Anonymous

at 50mph, how fast is the ball moving?

2007-06-30 06:36:47 · 7 answers · asked by Weezy J 3

We define "Present" as an instant, a very small interval of time.
We define "Past" and "Future" in relation to the Present.
Since, mathematically, to the limit, the Present is an interval of time equal to 0 (just zero), Present can't exist, nor, consequently, Past and Future...
However, we seem to agree that time came to existence at the Big-Bang and will cease to "exist" at the big-crunch (if it happens). So we must accept that time exists, and that it flows in one direction only: from past to future. However, Hawkins says that if the Universe is to go towards a big crunch, at the maximum expansion, time would reverse its flow!
Seems like a paradox. Maybe "all" "times" exist... at the same time?
Quantum leap theory is that all instants in time are present... at the same time... Human concept? Your ideas?

2007-06-30 05:54:30 · 19 answers · asked by just "JR" 7

A couple of months ago I got really obsessed about time travel following Eistien's theory's on it and I found that time travel was possible both ways just very hard to go back in time but while lookin at these theory's I found that it's possible to make the body respire backwards at speeds way faster then the speed of light if done in a gravitational enviroment although it is hard to control it can make anything do a course backwards.

2007-06-30 05:15:24 · 8 answers · asked by Anonymous

It's a kind of rare point of view in which the energy it's always expanding and that it seems to me that gravity it's been seen as a process of expanding energy of the matter instead of an attracting force. I don't really understand it. Can somebody explain it briefly to me?

2007-06-30 04:30:30 · 2 answers · asked by timmysanz 2

2007-06-30 04:16:25 · 6 answers · asked by ARUNA K 1

2007-06-30 04:03:19 · 4 answers · asked by kishan j 1

If you could tape-record your thoughts, you would find
a) one central thought and multiple, related subsidiary thoughts
b) an endless flow of ideas that constantly shifts and changes
c) a system of hierarchically organized cognitions
****d) an organized system of parallel thoughts

2007-06-30 03:32:00 · 3 answers · asked by x3KEvin 1

I need the math formula To figure the beam with of a police radar gun.
The specs in the owners manual says beam with is 12 degrees of arc.
What formula would I use to figure the beam width at different distances.

2007-06-30 01:32:20 · 2 answers · asked by stanley d 1

A monochromatic light beam with a quantum energy value of 3.0 eV is incident upon a photocell. The work function of the photocell is 1.6 eV. What is the maximum kinetic energy of the ejected electrons?

2007-06-29 22:43:32 · 3 answers · asked by Anonymous

We always measure the amount of changes by time and also we refer that changes to time, is that really happens in our actual life?

2007-06-29 19:18:53 · 3 answers · asked by M.Ali 2

the plane y + z =3 intersects the cylinder x^2 + y^2 = 5 in an ellipse. Find the parametric equations for the tangent line to this ellipse at the point (1,2,1)
Additional Details

Well i believe i let x = cost and y=sint and z=3-sint but then do i take the derrivate of each and then just plug in the point? it seems to straight forward. please help.

2007-06-29 19:01:29 · 2 answers · asked by Anonymous

Sitting under a tree is cooler than sitting under a sheet of cloth, for example. Why should that be?

This question was actually already asked 2 weeks ago, but I wasn't happy with the answer. The answer suggested then was that wind can blow easier in the tree shade, which I did not find convincing. I have two ideas:

(1) The tree shade is thicker, there are lots of leaves, so it insulates better

(2) The tree has to keep itself relatively cool to continue photosynthesis, so it cannot transfer as much heat downwards.

I think that explanation 2 is correct. Explanation 1 would only delay the time it takes for the heat to be transferred down, not eliminate it altogether.

I would be grateful for any alternative explanations, or supporting evidence for the explanations I thought of.

Thanks! Eyal

2007-06-29 17:33:03 · 10 answers · asked by eyal 1

2007-06-29 16:39:57 · 15 answers · asked by sw 1

2007-06-29 15:00:43 · 6 answers · asked by sar 1

2007-06-29 14:21:05 · 3 answers · asked by Johnny Bond 1

http://en.wikipedia.org/wiki/Philadelphia_Experiment

2007-06-29 12:14:44 · 5 answers · asked by laynep123 1

Why do you always choose Bekki B's answers as best? I give good answers, too! I'm a people person! What is wrong with you people???

2007-06-29 11:20:52 · 20 answers · asked by Anonymous

I'm trying to describe the sound you hear when a vehicle passes another on the highway, something like "whoosh," and on the racetrack like "vroom."

I feel like a little sheepish asking, but I need to do a presentation for a client and his minions, and I don't want to stammer through it.

Right now I'm describing it as, "you know that sound that one car makes when it passes another car?"

Thanks for your help.

2007-06-29 10:52:26 · 7 answers · asked by LJR 2

in a sound wave it is molecules air
in a water wave it is drops of water
in an electron is is ?

2007-06-29 10:51:16 · 7 answers · asked by Lobster 4

2007-06-29 10:47:35 · 10 answers · asked by mau 1

A 1.00-m long string with a mass of 15.0g is placed under a tension on 35.0 N. It is plucked so it vibrates in its fundamental standing wave mode. What are the frequency and wavelength of the sound. (Assume a temperature of 20°C - therefore the speed of sound through the air is ≈ 343 m/s)

2007-06-29 10:18:03 · 3 answers · asked by James Z 1

A greasy flatbed truck is carrying a crate weighing 2.0 kN. The truck accelerates uniformly from rest to a speed of 40 km/h in a distance of 40.0 m. In that time, the crate slides 1.0 m back toward the end of the truck. Compute the coefficient of friction between bed and box.

2007-06-29 09:32:35 · 2 answers · asked by long t 2

Not looking for answers just looking for a walk through on any of these questions.

A cart of mass 1.5 kg is given an initial velocity of 2.1 m/s up a uniform incline at an angle of 3.3 degrees with horizontal. Assuming that the only forces acting on the cart are gravitational and normal forces, determine the following:

*How much work is done by gravity on the cart, and how much work does the cart do against gravity, as the cart travels 3.25 meters along the incline?
*By how much does its kinetic energy change during this displacement?
*Using energy considerations determine how fast the cart is moving at the end of this displacement.
*How are work done by the cart and its kinetic energy change related?
*How would the quantities calculated in this problem differ if the cart had ended up 3.25 meters down the incline?

2007-06-29 09:00:56 · 1 answers · asked by e=mc^2 1

A skateboarder moves at v = 4.4 m/s along a horizontal section of a track that is slanted upward by 48° above the horizontal at its end, which is h = 0.48 m above the ground. When she leaves the track, she follows the characteristic path of projectile motion. Ignoring friction and air resistance, find the maximum height H to which she rises above the end of the track.

2007-06-29 08:37:03 · 4 answers · asked by M&M 2

Two masses are hung from a meterstick, which has a mass of 0.248 kg. The first mass is 0.278 kg and it is suspended from the 22.9 cm position and second mass is 1.773 kg and it is suspended from the 75.6 cm position. At what position along the meterstick should you place a fulcrum so that the entire system (meterstick plus the two masses) is balanced?

2007-06-29 08:19:21 · 1 answers · asked by YoDaddyHoe 1

A 30.0 g object is attached to a horizontal spring with a force constant of 5.0 N/m and released from rest with an amplitude of 25.0 cm. What is the velocity of the object when it is halfway to the equilibrium position if the surface is frictionless?

2007-06-29 08:13:15 · 2 answers · asked by Katie 1