Physics - December 2007

how are you supposed to answer this i dont gett it.,

Pretend that you are the size of an atom, observing a reaction between a potassium atom and a fluorine atom. Write an account of the formation of an ionic bond as the atoms react. Tell what happens to the valence electrons on each atom and how each atom is changed by losing or gaining electrons.

2007-12-09 05:12:52 · 1 answers · asked by Emily:) 1

2007-12-09 04:22:08 · 2 answers · asked by me samir4u 1

waves have phases right?
can someone please tell me what the phases of waves are and a SHORT, SWEEEEET, and SIIMPLE definition of each wave phase?


tank u

2007-12-09 03:58:59 · 5 answers · asked by luvalwayz_divya 1

A grinding disc is turning 12900 rpm. The disc has a diameter of 20.0 cm. Calculate the smallest cohesive force holding a 1.00 g bit of grit on the edge of the disc.

minimum Centripetal Force = ________________ N

2007-12-09 03:51:12 · 3 answers · asked by Anonymous

The rotational speed on a platform remains unchanged but the distance from the center of the platform is doubled. This will cause the rotational speed to

a. be quadrupled.
b. be tripled.
c. remain the same.
d. be doubled.
e. be cut in half.

2007-12-09 03:33:23 · 2 answers · asked by Anonymous

Jill of the Jungle swings on a vine 6.1 m long. What is the tension in the vine if Jill, whose mass is 61 kg, is moving at 2.9 m/s when the vine is vertical?
N

2007-12-09 03:17:25 · 3 answers · asked by Amber G 2

i'm just wondering.......

2007-12-09 02:42:25 · 3 answers · asked by Stupid 2

Light in air strikes a transparent plate of an unknown material at an angle of incidence of 60 degrees. Part of the beam is reflected and part refracted. A measurement shows that the angle between the reflected and refracted beams is 90 degrees with each other. What is the index of refraction of the material?

2007-12-09 02:09:25 · 3 answers · asked by jb143 1

does it have a formula?

2007-12-09 02:02:49 · 2 answers · asked by Wxzy 2

2007-12-09 01:26:36 · 1 answers · asked by 562cheese 2

An electron is released from rest in a uniform electric field of magnitude 8 * 10^4 v/m directed along the positive x-axis. The electron is displaced 0.5m in the direction opposite E.

a. Find the change in the electric potential between the point of start and finish.

b. Find the change in the potential energy of the electron.

c.Find the speed of the electron then convert the energy values into eV.

2007-12-08 22:56:07 · 1 answers · asked by gladiator 1

2007-12-08 22:55:11 · 4 answers · asked by waleed 1

2007-12-08 22:43:33 · 4 answers · asked by flygirl 2

since electrons are so much smaller than protons, why are the magnitudes of their charges the same?

2007-12-08 22:23:52 · 3 answers · asked by Anonymous

Before time was measured in seconds, minutes, and hours were there any other forms of time measurement?

Apparently the first people to subdivide time where the Egyptians around 2000bc.
So were there forms of time measurement that sprung up throughout history that have since died out, or did all time measurement spread across the world from Egypt?

2007-12-08 19:36:49 · 9 answers · asked by basisdnb 1

2007-12-08 19:03:35 · 5 answers · asked by Anonymous

i was told i dont have a personality, what does that mean?

2007-12-08 17:22:24 · 22 answers · asked by Anonymous

A centrifuge is a common laboratory instrument that separates components of differing densities in solution. This is accomplished by spinning a sample around in a circle with a large angular speed. Suppose that after a centrifuge in a medical laboratory is turned off it continues to rotate with a constant angular deceleration for 24.7 s before coming to rest.
(a) If its initial angular speed was 2870 rpm, what is the magnitude of its angular deceleration?
...rev/s2
(b) How many revolutions did the centrifuge complete after being turned off?
...rev

2007-12-08 17:20:47 · 3 answers · asked by p0oh 1

inside the liquids or gases coz they do not posses cohesion.

longitudinal waves can be transmitted inside the liquids or gases coz they posses volume elasticity.


what does it mean?

2007-12-08 16:30:03 · 2 answers · asked by Barbie d 1

a potter's wheel moves from rest to an angular speed of 0.20 rev/s in 30.0 s. Assuming constant angular acceleration, what is its angular acceleration in rad/s^2?

2007-12-08 15:56:51 · 2 answers · asked by Anonymous

Four guys are lined up in front of a firing squad:

http://s226.photobucket.com/albums/dd11/jackphotos123/?action=view¤t=FiringSquadRiddle.jpg

They are told this:
"Two of you guys are wearing red hats and two of you guys are wearing blue hats. If you can tell me what color hat you are wearing and why, I'll let you walk away and live."

After a few seconds, one guy raises his and with the answer. Which guy was it and how did he know?

2007-12-08 15:49:34 · 7 answers · asked by Anonymous

A force of 15.78 N is applied tangentially to a wheel of radius 0.340 m and gives rise to an angular acceleration of 1.20 rad/s^2. Calculate the rotational inertia of the wheel.

2007-12-08 15:43:20 · 2 answers · asked by hmm 1

emits an electron to become a proton? Do the quarks somehow change their charge?

2007-12-08 15:31:23 · 3 answers · asked by Anonymous

A solid concrete block weighs 174 N and is resting on the ground. Its dimensions are 0.400 m 0.200 m 0.100 m. A number of identical blocks are then stacked on top of this one. What is the smallest number of whole blocks (including the one on the ground) that can be stacked, so that their weight creates a pressure of at least one atmosphere on the ground beneath the first block? (Hint: First decide which face of the brick is in contact with the ground.)

2007-12-08 15:20:48 · 2 answers · asked by koetjet24 1

When you take a bath, how many kilograms of hot water (48°C) must you mix with cold water (10°C) so that the temperature of the bath is 36°C? The total mass of water (hot plus cold) is 192 kg. Ignore any heat flow between the water and its external surroundings.

2007-12-08 15:19:16 · 3 answers · asked by koetjet24 1

A thermos contains 145 cm3 of coffee at 85°C. To cool the coffee, you drop two 13 g ice cubes into the thermos. The ice cubes are initially at 0°C and melt completely. What is the final temperature of the coffee? Treat the coffee as if it were water. (See Table 12.2 and Table 12.3 for appropriate constants.)

http://kooch.gamedaemons.net/pictures/12-02tab.gif
http://kooch.gamedaemons.net/pictures/12-03tab.gif

2007-12-08 15:17:40 · 2 answers · asked by koetjet24 1

2007-12-08 14:48:16 · 6 answers · asked by jay 1

2007-12-08 14:41:12 · 1 answers · asked by Eric S 1

obviously it wouldn't matter if it were a loud rasberry, being as the speed of light is so many times faster than the speed of sound. but what if it were a "silent but deadly", would you still smell it?
what is the speed of smell?
has anyone ever tried to measure it?

2007-12-08 14:21:13 · 9 answers · asked by biodegradable insane asylum 5

2007-12-08 14:19:56 · 3 answers · asked by Baby Jack born 4/5/09 4