Physics - November 2007

do sunlight or like a regular home light say, in your kitchen have stronger uv ray?


this is for my science fair.

2007-11-24 10:16:00 · 3 answers · asked by :] 1

Specifically The Equation. I know it is 1/2 x Mass x Velocity but what does the 1/2 bit mean? Half Of What

2007-11-24 09:57:47 · 3 answers · asked by The Wonderful Me 4

Assume a car is going 10 mph on an icy road. Does it really get better traction if driving in "Low" than in "Drive"? And if so, why? I don't understand the physics.

2007-11-24 09:57:16 · 2 answers · asked by Halbert 2

Well, I've researched my textbooks and wikipedia.
I think I may know the general idea of what it is, but I want to be sure.
This is what I think....

-So I read that Acceleration is the rate of change, and a Newton is the force required to accelerate 1 kg of a substance by 1 meter per second squared (1 kg * m / s2).
So if I have my meaning of Acceleration correct, then if something had an acceleration of 5 Newtons, then for every second passed, 1 kg of that substance would speed up 5 meters per second more? So if it starts out at 10 m/s, then in 3 seconds it would be going at a speed of 25 m/s? Is that right?

And I know that a Joule is "the energy expended by a force of one newton moving an object one meter along the direction of the force." but can someone explain that to me more?
So...if a block of concrete that weighed 1 kg was sliding down a hill with a force of one newton (meaning it sped up 1 meter more per second?) then for every meter it slid, that would be 1 Joule?

2007-11-24 09:54:47 · 3 answers · asked by silvershadow0001 1

are located in space? How can we observe photons traveling from point A to point B?

In other words, how is it possible for a photon with no spatial dimensions to be located in space, or be said to stand in some relation to other objects in space? Is having "no spatial dimensions" the same as being "not located in space?"

How does science account for this? I know this is a tall order for an online forum, so I would love it if someone could direct me to a reliable source that would address this question.

2007-11-24 09:37:07 · 3 answers · asked by Pull My Finger 7

Radon - 212 has a half-life of 24 minutes. Show that if you start with 96mg of radon-212 that you will have 91 mg of polonium-208 two hours later (and not 93 mg).

2007-11-24 09:35:57 · 1 answers · asked by ... 2

in relation to physics.

2007-11-24 09:20:00 · 1 answers · asked by diablo_blaze7 2

Late in the twentieth century, a series of observations and theories arose, not related to the mind or consciousness, but purely on the agenda of mainstream particle physics and cosmology.From the beginning of quantum physics in the early twentieth century, physicists have found, strangely, a role in physics for human consciousness and the mind. This role has in fact been too strange for mainstream physics, which has proceeded without the mind.

2007-11-24 09:08:42 · 5 answers · asked by bhattathiry 1

2007-11-24 09:08:16 · 18 answers · asked by Anonymous

2007-11-24 08:56:00 · 3 answers · asked by Pull My Finger 7

A man 6ft tall walks at a rate of 5ft/s away from a light that is 15ft above the ground. When he is 10ft away from the base of the light,

a.) At what rate is the tip of his shadow moving?
b.) At what rate is the length of his shadow changing?

Thanks SO much.
Any Help would be great.
Thanks

2007-11-24 08:05:07 · 1 answers · asked by mastriannichris 1

I mean people with scientific credentials.

2007-11-24 08:04:37 · 4 answers · asked by Anonymous

2007-11-24 07:47:24 · 4 answers · asked by Anonymous

A skateboarder is slowing down at a rate of .70 m/s^2. At the moment he is moving forward at 1.5 m/s, he throws a basketball upward so that it reaches a height of 3.0 m, and then he catches it at the same level it was thrown without changing hie position on the skateboard. Determine the vertical and horizontal components of the ball's velocity relative to the skateboard when the ball left his hand.

Please help me with this one....I'm stumped! Thanks!

2007-11-24 07:13:24 · 1 answers · asked by ☺♠JonasJay♫♦ 5

Two painters are standing on a 5.0 mg long scaffold. Each painter weighs 833 N. 1 painter is standing 2.0 mg from the left end and 1 is standing .50 mg from the right end. The scaffold weighs 285 N. What is the tension in the 2 cables supporting the scaffold?

2007-11-24 07:02:47 · 1 answers · asked by kaynaptx 1

2007-11-24 06:11:45 · 6 answers · asked by prashnjain3 1

How much work is done in moving Avogardo's number of electrons from an inital point where the electric potential is 9.00V to a point where the potential is -5V?

This is how I attempted the question
Delta V = V2 - V1 = -5 - 9 = -14V
W = U = Vqe

2007-11-24 06:11:00 · 2 answers · asked by Anonymous

as you approach the speed of light time slows down, and at light speed time stops. so wouldn't that meant that light travels instantaneously.

2007-11-24 06:03:37 · 5 answers · asked by Anonymous

2007-11-24 05:50:14 · 5 answers · asked by IcanHelpyou:) 3

A spring has a force constant of 600.0 N/m.

(a) Determine the potential energy stored in the spring when the spring is stretched 3.90 cm from equilibrium.

(b) Determine the potential energy stored in the spring when the spring is stretched 2.99 cm from equilibrium.

2007-11-24 05:38:44 · 1 answers · asked by Anonymous

A 50.0 kg diver steps off a diving board and drops straight down into the water. The net force when in the water is an upward 1350 N. If the diver comes to rest 4.8 m below the water's surface, what is the total distance between the diving board and the diver's stopping point underwater?

2007-11-24 05:37:44 · 1 answers · asked by Anonymous

Please explain the theory. The guys feel better when a conversation is technical.

2007-11-24 05:31:14 · 2 answers · asked by Margy 3

I think it is because of the white coating. It stores energy and then releases it as light, but, I could not explain the flicker. Do you know why?

2007-11-24 05:17:49 · 3 answers · asked by Anonymous

2007-11-24 05:04:20 · 2 answers · asked by Anonymous

Astronauts who spend long periods in outer space could be adversely affected by weightlessness. One way to simulate gravity is to shape the spaceship like a bicycle wheel that rotates about an axis just like a wheel, with the astronauts walking on the inside of the "tire."
Consider
a) how objects fall
b) the force we feel on our feet
c) any other aspects of gravity you can think of.

Please help, thank you!

2007-11-24 05:01:14 · 1 answers · asked by Kiwikahuna 2

2007-11-24 04:56:27 · 6 answers · asked by Anonymous

In relation to physics.

2007-11-24 04:41:39 · 3 answers · asked by diablo_blaze7 2

2007-11-24 04:28:16 · 2 answers · asked by Ashwin K 1

A 2-kg block and 8-kg block are both attached to an ideal spring (k = 200 N/m) and both are initially at rest on a horizontal frictionless surface.
A 100-gram ball of clay is thrown at the 2-kg block, moving horizontally with speed v when it hits and sticks to the block. 8-kg block is held still by a removable stop. Spring compresses a maximum distance of 0.4 m.

a. Energy stored in the spring at max. compression.
b. Speed of the clay ball and 2-kg block immediately after the clay sticks to the block but before the spring compresses significantly.
c. Initial speed v of clay

An identical ball of clay is thrown at another identical 2-kg block, but this time the stop is removed so that the 8-kg block is free to move.

d. Max. compressionn of the spring will be greater than, equal to, or less than 0.4 meter?
e. State principles used to calculate v of 8-kg block at the instant that the spring regains its original length. Write equations and show numerical substitutions.

2007-11-24 04:25:20 · 2 answers · asked by M4tr!x 2

Would you assume the final velocity to be zero?...and if anyone can help it will be greatly appreciated..for some reason these acceleration problems have been causing me problems..thanks

2007-11-24 04:20:10 · 4 answers · asked by ... :) 2