Physics - March 2007

A sailboat is sailing due east at 8.20 mph. The wind appears to blow from the southwest at 10.9 mph. What is the true wind speed? What is the true wind speed if the wind appears to blow from the northeast at 10.9 mph?

2007-03-14 15:53:34 · 2 answers · asked by RelientKayers 4

You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to the ground. You find the arrow stuck in the ground 61.0 m away, making a 2.00 degrees with the ground. How fast was the arrow shot?

2007-03-14 15:52:31 · 2 answers · asked by RelientKayers 4

How does the relationship of incident to reflected ray relate to the reflection of water waves moving perpendicular to a barrier? Please help, i'm being pwn3nd by this :(

2007-03-14 15:45:29 · 2 answers · asked by goodbassistsarehardtofind 2

Imagine you are in a vehicle travelling at the speed of light.
You turn your headlights on.
Does anything happen?

2007-03-14 15:31:34 · 14 answers · asked by Anonymous

short answers, not long, good luck!

1. How is energy related to motion?
2. How is energy related to force?
3. How is energy related to power?
4. Two cars have the same momentum. One car weighs 5000 N and the other weighs 10,000 N. Which car has a greater kinetic energy? Explain your answer.

2007-03-14 15:25:04 · 5 answers · asked by taylor_travers098 2

2007-03-14 15:14:06 · 1 answers · asked by wencar29 1

You are testing a new amusement park roller coaster with an empty car with a mass of 108 kg. One part of the track is a vertical loop with a radius of 12.0 m. At the bottom of the loop (point A) the car has a speed of 25.0 m/s and at the top of the loop (point B) it has speed of 8.00 m/s.

As the car rolls from point A to point B, how much work is done by friction?
Use g = 9.81 m/s^2 for the acceleration due to gravity.

2007-03-14 14:30:36 · 2 answers · asked by eric 2

A block of ice with mass 5.80 kg is initially at rest on a frictionless, horizontal surface. A worker then applies a horizontal force \vec{F} to it. As a result, the block moves along the x-axis such that its position as a function of time is given by x(t)= ( 0.204 m/s^2) t^{2}+ ( 1.98×10−2 m/s^3) t^{3}.

Known Values from previous problems:

velocity of the object at time t = 3.80 s.
2.41 m/s

magnitude of \vec{F} at time t = 3.80 s.
4.98 N

would appreciate answer and/or explanation.

2007-03-14 14:19:32 · 2 answers · asked by eric 2

Where did the oxygen in Earth's atmosphere come from? How was the ozone play in the development of our current atmosphere?

2.Imagine that earth was not rotating and covered entirely with water rather then the current pattern of land and water. Assume that the sun is directly above the equator. What winds and pressure patters would occur?

3.What are the two ways that deforestation adds carbon dioxide to the atmosphere?

These are 3 question i need help on my homework if someone really smart can help me please because im almost finishing my studyguide and i have to study for that test tommorow(How can we study doing the study guide a day before the test and study with wrong answers?)

2007-03-14 13:45:57 · 4 answers · asked by Tha best!! 2

2007-03-14 13:43:34 · 3 answers · asked by Kriselle Y 1

I concocted this a while ago, and I thought I'd throw it out on the net to see why I'm wrong. So supposedly it's impossible for anything to go faster than light; this includes information. So considering this, what about information that is passed along a solid object. For example, if I have a really long diamond pole (diamond because it seems least likely to compress) and moved it forward an inch, that movement would manifest itself at the other end of the poll instantaneously no matter how long it is. I know that this is entirely impractically because the distances where it will matter to transmit information faster than the speed of light, are also the distances where it is impossible to create a stick that long. None the less, it is interesting to think about. I'm probably wrong though, so let me know.

2007-03-14 13:29:10 · 4 answers · asked by Aaron 2

Hi, can anyone explain to me 2 different ways to make laser, (like 2 ways how lasers are made). I am not looking to destroy people, I just wanted to know for a science project. Thank you.

2007-03-14 13:27:15 · 1 answers · asked by BroncosD 4

A ray of light incident upon a mirror makes an angle of 34.6° with the mirror. What is the angle between the incident ray and the reflected ray?

2007-03-14 13:23:57 · 1 answers · asked by drmarkmedman 1

Most liquids have a water base, but there is one liquid that doesn't have a water base (liquids that are diluted with water do not count). This liquid has a high density.

2007-03-14 13:11:33 · 6 answers · asked by HELP 1

2007-03-14 13:08:50 · 2 answers · asked by snr10182003 1

#1) The height of the projectile fired upward is given by the formula s=Vot-16t ^2, where s is the height and Vo is the initial velocity and t is time. Find time for a projectile to return to Earth if it has velocity of 200ft/s.

I know in this one, i solve for t, but distance would I use for s?

#2) . In Germany, there are no speed limits on some portions of highway. Others have a speed limit of 180 km/h (approximately 112 mph.) required to stop a car traveling at v kilometers per hour is d=0.019v^2+0.69v. Approximate to nearest tenth.

I don't get this one at all!!

#3) A model rocket is launched with an intial velocity of 200ft/s. The height h, of the rocket t seconds after the launch is given by h= -16ft^+200t. How many seconds after launch will rocket be 300 ft above ground? Round nearest hundredth of a sec.

2007-03-14 13:08:23 · 2 answers · asked by abe_cooldude 1

2007-03-14 13:05:22 · 1 answers · asked by marta 1

2007-03-14 13:03:32 · 2 answers · asked by mishel24 2

For a wavelength of 420 nm, a diffraction grating produces a bright fringe at an angle of 26°. For an unknown wavelength, the same grating produces a bright fringe at an angle of 34°. In both cases the bright fringes are of the same order m. What is the unknown wavelength?

2007-03-14 12:50:52 · 1 answers · asked by marinatedpickles 2

In IMAGE (click on link below for image) we see two blocks connected by a string and tied to a wall. The mass of the lower block is 1.0 kg; the mass of the upper block is 2.0 kg. Given that the angle of the incline is 31 degrees, find the tension in a) the string connecting the two blocks and b) the string that is tied to the wall.

LINK for image: http://img.photobucket.com/albums/v156/PNHTran88/02.jpg

Thanks!

2007-03-14 12:49:23 · 1 answers · asked by 123haha 1

is it true that you have to stay calm all the time when your always using telekinesis?

2007-03-14 12:46:43 · 4 answers · asked by josemenitsilvano 1

How many dark fringes will be produced on either side of the central maximum if light ( = 568 nm) is incident on a single slit that is 5.27 10-6 m wide?

2007-03-14 12:42:49 · 4 answers · asked by marinatedpickles 2

2007-03-14 12:42:00 · 5 answers · asked by Gypsy Gal 6

A mixture of red light (vacuum = 661 nm) and green light (vacuum = 551 nm) shines perpendicularly on a soap film (n = 1.35) that has air on either side. What is the minimum nonzero thickness of the film, so that destructive interference causes it to look red in reflected light?

2007-03-14 12:40:26 · 2 answers · asked by marinatedpickles 2

2007-03-14 12:37:54 · 3 answers · asked by Anonymous

Three small negatively charged metal spheres in vacuum are fixed on a horizontal straight line, the x-axis. One (-15.5 µC) is at the origin, another (+7.00 µC) is at x = 2.0 m, and the third (-50.0 µC) is 1.0 m beyond that at x = 3.0 m. Compute the magnitude of the net electric force on the last sphere due to the other two.


pls show me the steps you took to get your answer and what you get..thanks!!

2007-03-14 12:31:00 · 3 answers · asked by aldkjasdk 2

At a given instant three electrons, in vacuum, happen to lie on a straight line. The first and second are separated by 2.00E-6 m, while the second and third are 7.00E-6 m apart. What is the magnitude of the net electrostatic force on the middle electron, the second one?

2007-03-14 12:27:27 · 2 answers · asked by Khoi 1

In a Young's double-slit experiment, the wavelength of the light used is 510 nm (in vacuum), and the separation between the slits is 2.40 10-6 m. Determine the angle that locates each of the following.
(a) the dark fringe for which m = 0
°
(b) the bright fringe for which m = 1
°
(c) the dark fringe for which m = 1
°
(d) the bright fringe for which m = 2
°

2007-03-14 12:24:19 · 3 answers · asked by marinatedpickles 2

2007-03-14 12:22:42 · 8 answers · asked by Aztec_Explorer 1

The geiger Watches are a little too expensive and I don't want to buy a dosimeter. A battery operated digital Counter that I could buy at a store would be what I am looking for. Where can I get one?

2007-03-14 12:06:16 · 3 answers · asked by Sam Y 3