Physics - April 2007

Einstein's a great prominment man. He speculated that taking out the sun, would take roughly 8min to the light to get to us, and also 8min when the gravity is extracted from the sun.
Then Earth would be the 3rd planet to drift away, 4mins later Mars, 7min astro belt, 12 Jupitor, ect..

So does gravity travel the speed of light? 300,000 km/sec???

2007-04-24 17:23:19 · 8 answers · asked by Anonymous

How long must a simple pendulum be if it is to make exactly six swings per second? (That is, one complete vibration takes exactly 0.333 s.)

Answer in meters of course.

2007-04-24 17:00:24 · 3 answers · asked by Jessie L 2

Why do different text books say there are different numbers of electrons in the atom's shells?
One text book says the first shell holds two electrons, the second 8 and the third 8 as well, but the other book says the first holds 2, second 8 and the third is 18. What the??? Which one is correct? Why is it different?

2007-04-24 17:00:03 · 2 answers · asked by dogvirusdoo 1

Please if you can, answer these 4 questions. They are to help me prepare my grand daughter for a test. I will give points.

1. A student exerts a force of 100 N to push a wagon with a mass of 20.0 kg a distance of 35.0 m . What is the work of the student to push the wagon?

2. A person exterts a force of 300N on a cart through a distance of 100 cm. What is the work done on the cart?


3. A 7.0 kg package is held 2.0 m above the ground. How much work is done on the package?


4. If a student applies 200 J of work on a cart that moved 25.0 m, then what is the forced used?


Please type how you got your answer and the formula you used, if you can. That would be fantastic. Thankyou so much for your help.

2007-04-24 16:48:26 · 2 answers · asked by Grandpa Donald 1

To take a clear picture of an image in a flat mirror, should the camera be focused on the image or on the surface of the mirror?

2007-04-24 16:23:50 · 1 answers · asked by Hannah 1

a)a cell with copper and zinc electrodes in an acid electrolyte.
b)a cell with 2 copper electrodes in a salt water electrolyte
c) cell with zinc and carbon electrodes in distalled water electrolyte

2007-04-24 15:45:00 · 2 answers · asked by Cutie 4

A block is released from rest at height d=40 cm and slides down a frictionless ramp and onto a first plateau, which has length d and where the coefficient of kinetic friction is 0.50. If the block is still moving, it then slides down a second frictionless ramp through height d/2 and where the coefficient of kinetic friction is again 0.50. If the block is still moving, it then slides up a frictionless ramp until it (momentarily) stops. Where does the block stop? If its final stop is on a plateau, state which one and give the distance L from the left edge of that plateau. If the block reaches the ramp, give the height H above the lower plateau where it momentarily stops.

2007-04-24 15:42:34 · 2 answers · asked by H.A. 2

1. Describe what happens to a ray of light as it travels from air into a more dense material, then back into air.
2. In which substance, water or the sold block, do you think light travels faster? What evidence to support the answer?
3. How does the anglie of incidence in air compare to the angle of emergence in air?

2007-04-24 15:35:18 · 2 answers · asked by Anonymous

Speakers A and B are vibrating in phase. They are directly facing each other, are 8.2 m apart, and are each playing a 71.0 Hz tone. The speed of sound is 343 m/s. On the line between the speakers there are three points where constructive interference occurs. What are the distances of these three points from speaker A?

=?m (nearest)
=?m (middle)
=?m (farthest)

I am having a hard time getting the answer. I worked the problem multiple times. For the other answers, I am having the same problem. for my first distance I got the 343/71.0 = 4.83. Then 8.2 - 2x= m 4.83 then I divided that by 2 and got 3.9 - x = m(2.3135)
for the speaker thats farthest away I know you do the length that they are apart, 8.2, minus your nearest distance you got for part A

I just cannot get the correct answer..... grrrrr.....

2007-04-24 15:24:34 · 2 answers · asked by ..*Real-ality*.. 3

i had a lil debate with my physics teacher and he pointed out that it was impossible to make, because u had to fuse krypton and that other one i can't remember its name right?

2007-04-24 15:07:33 · 8 answers · asked by ‡ Edgar ‡ 2

2007-04-24 14:51:55 · 7 answers · asked by Anonymous

A 0.750kg block is firmly attached to a a very light spring (k=275N/m). It is noted that the block-spring system, when compressed 8.0cm and released, stretches out 3.6cm beyond the equilibrium position before stopping and turning back. What is the speed of the block as it passes the equilibrium position for the first time after being released? THE ANSWER IS 1.03m/s, HOW DO YOU GET IT?

2007-04-24 14:46:34 · 2 answers · asked by Anonymous

Physical science question

2007-04-24 14:45:06 · 2 answers · asked by Anonymous

3049decays/minute over a period of 5.00days. What is the half-life T(1/2) of this isotope?

2007-04-24 14:30:00 · 2 answers · asked by Anonymous

If so, what does the curved line mean? I know in distance time graph you can, and that means that the object is accelerating.

A question in my book asks me to "plot the data on a velocity-time graph. Connect the points with a smooth curve".

I'm confused because in class, the teacher has never mentioned curved lines in v-t graphs.

2007-04-24 14:23:24 · 4 answers · asked by Anonymous

It is very difficult for me to pose this question in this text format, but the link http://216.101.58.17/hs/lkruse/AP/Optics%20worksheet%2003-04.htm will direct you to the question I am having so much difficulty with. I really need some nice person to show me how to do number 1, problems (a.) through (e.)ii. I would really appreciate iit.

2007-04-24 13:48:10 · 1 answers · asked by Scratch22 1

can you be bad at math and do theoretical physics, astronomy, cosmology?

2007-04-24 13:26:28 · 4 answers · asked by Anonymous

The electric field intensity between two charged plates is 1.5*10^3 N/C. The plates are 0.060 meters apart. What is the electric potential difference, in volts, between the plates?

Please help me with this problem.
I don't understand it.

2007-04-24 12:49:07 · 4 answers · asked by vicky p 1

science trivia! please help!

2007-04-24 12:46:39 · 3 answers · asked by !@!@!@! & 1

Please help me with this problem.
I don't understand it.

2007-04-24 12:41:15 · 4 answers · asked by vicky p 1

A positive charge of 1.0*10^-5 C, shown in the picture link, experiences a force of 0.30 N when it is located at a certain point. What is the electric field intensity at that point?

*picture link: http://img340.imageshack.us/img340/4786/physics67bu5.jpg

Please help me with this problem.
I don't understand it.

2007-04-24 12:36:21 · 3 answers · asked by vicky p 1

2007-04-24 12:27:43 · 4 answers · asked by patricia p 1

#1) the gravitational force between two objects (mass1= 10 kg, mass2=6 kg) is measured when the objects are 10 centimeters apart. if the 10 kg is replaced with 20kg mass and the 6kg mass is replaced with 12kg mass, how does the new gravitational attraction compare to the first one measured?

#2)the gravitational force between two objects (mass1= 10 kg, mass2=6 kg) is measured when the objects are 10 centimeters apart. if the distance between then is increased to 40 centimeters, how does the new gravitational attraction compare to the first one measured?

#3) The gravitational force between two objects (mass1=1kg, mass2=2kg) is measured when the objects is reduced to 4 centimeters, how does the new gravitational attraction compare to the first one that was measured?

Please help me.... i really need to get these right! its very important and this is not my best subject..... And lots of other homework!!! please HELP!!

2007-04-24 11:57:34 · 1 answers · asked by nootherlikeme 3

I am having trouble with this particular problem of the section.

An alpha particle (Z = 2, mass 6.64 10-27 kg) approaches to within 1.10 10-14 m of a carbon nucleus (Z = 6).
(a) What is the maximum Coulomb force on the alpha particle?

(b) What is the acceleration of the alpha particle at this point?

(c) What is the potential energy of the alpha particle at the same time?

2007-04-24 11:55:31 · 1 answers · asked by russwalker_05 2

Assume teleportation technology exists.

You have two doorways. When you pass through one you teleport through time and space and exit out the other doorway.
(Basically like the two doorways in the halo level with the river in the middle.)

Assume that if you place one of the doorways on its side, it will fit through the other doorway.

What would happen if you placed one doorway into its reciprocal doorway?

2007-04-24 11:17:58 · 5 answers · asked by Tomaltchach 2

the resistance of a certain wire is 10 ohms.What would the resistance of the same wire be if it were 2x as long?If it were 2x as thick?plz explain

2007-04-24 10:35:50 · 3 answers · asked by kobay 2

2007-04-24 10:24:11 · 8 answers · asked by BIG G 2

plz help me with some physics hw

2007-04-24 10:10:09 · 2 answers · asked by Amy C 1

Please answer following three questions

i. Silver is the best conductor than copper, then why Copper wires are generally used in daily life instead of silver wires?
ii. What will be the frequency of 3v DC battery?
iii. In which circuit analysis techniques KCL and KVL are used.

2007-04-24 09:56:33 · 2 answers · asked by medious009 1

pelase see http://sit.edu.pk/question/Mesh%20Analysis_Q2.doc

2007-04-24 09:49:24 · 2 answers · asked by medious009 1