Science & Mathematics - 20 December 2007

At what point can you no longer add more heat (can't get hotter than the heat source which would be the surface of the sun) but what happens the the rest of the energy that you are focusing into that point, dose it just disapate faster and how much increase in heat do you get out of each multipel focus of the beam of sunlight.
I'v tried to look this up and found different answers but can not get the whole thing but together if someone could explaine it in laymans terms I would really appreciate it
Thank you in advance if you can help.
John k

2007-12-20 14:24:34 · 3 answers · asked by John K 2 in Physics

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2007-12-20 14:23:53 · 16 answers · asked by Anonymous in Astronomy & Space

A 1.00×104kg railroad car is rolling at 6.00m/s when a 8000kg load of gravel is suddenly dropped in.

Kevin is standing on a sheet of ice that covers the football stadium parking lot in Buffalo, New York; there is negligible friction between his feet and the ice. A friend throws Kevin a ball of mass 0.400kg that is traveling horizontally at 10.0 m/s. Kevin's mass is 67.4 kg. If Kevin catches the ball, with what speed v(f) do Kevin and the ball move afterward? I got this right, which was 5.9 cm/s, but I don't understand how to get the second part: If the ball hits Kevin and bounces off his chest horizontally at 7.50 in the opposite direction, what is his speed v(f) after the collision?

2007-12-20 14:20:30 · 3 answers · asked by nothankyou1110 2 in Physics

1. The number of which atomic particle determines the identity of an element? (3 choices)

proton
neutron
electron

2. Which of the following has almost no mass? (3 choices)
proton
neutron
electron

3. Which of the following orbits the nucleus? (3 choices)
proton
neutron
electron

4. Metals are: (3 choices)
poor conductors.
brittle.
malleable.

5.The principal quantum number indicates the: (3 choices)
pair of electrons.
main energy level.
subshells.

6. The outer energy level of a noble gas is: (3 choices)
empty.
filled.
half-filled.

7. The modern periodic law states that properties of elements are functions of their: (3 choices)
atomic numbers.
atomic masses.
electrons.


**don't worry more questions to come :)

2007-12-20 14:15:47 · 7 answers · asked by Anonymous in Chemistry

'coldest fire'

2007-12-20 14:14:25 · 2 answers · asked by Thomas E 7 in Chemistry

A m1 = 4.80 kg block on a smooth tabletop is attached by a string to a hanging block of mass m2 = 2.30 kg, as shown in Figure 6-29. The blocks are released from rest and allowed to move freely.

the figure is at this url.... http://www.webassign.net/walker/06-29alt.gif

Find the Acceleration of the blocks and the tension in the string
-->acceleration should be in m/s^2
-->tension should be in newtons


If you could solve this it would be much appreciated!! thanks

2007-12-20 14:12:59 · 7 answers · asked by xoxo-oth 2 in Physics

determine the volume of stock acid required to prepare 500ml of 0.5mol/l hydrochloric acid. Assume the stock acid is 38% by mass hydrogen chloride and has a density of 1190kg/ m3 (1.190g/ml).

2007-12-20 14:11:55 · 4 answers · asked by Anonymous in Chemistry

2007-12-20 14:11:37 · 1 answers · asked by martha.gibbons 1 in Geography

how much will 3.00 moles of o2 weigh in grams

32.0 grams
_________
1mole

and the harder one is how much volume in l will 56.0 grams of CO(g) have at stp? 1st i have to change gas into moles then i have to change moles into litres

2007-12-20 14:10:46 · 6 answers · asked by Anonymous in Chemistry

2007-12-20 14:10:28 · 7 answers · asked by martha.gibbons 1 in Geography

My textbook says that:

The magnetic north pole is the magnetic S pole which is in northern canada and isn't exactly the geographical north pole.

Also, it says that the magnetic south pole is the magnetic N pole which is in antartica (or something).

The thing that I'm confuzed about is does a compass needle point to magnetic N (magnetic South) or the magnetic S (magnetic North) pole. And how can a compass help us determine which way north is if it isn't even the real direction of the geographical north!

2007-12-20 14:09:16 · 6 answers · asked by ? 1 in Geography

This question is a little complicated, but I need to know this for a book I'm writing. Say someone is shot in the head. lol. If the round just happened to only hit the part of the brain responsible for rational thought and consciouness and did not affect the more vital parts of the brain, could the person not only live, but function?

Meaning, if the part of the brain that was damaged was intact enough to provide just enough for the person to be aware of their surroundings and in a sense consciouness, would they be able to walk around, have decent motor skills, and do things such as open doors, walk down stairs, maybe even fight?

I know that if you did happen to be shot in the head and live you would probably be unconsciouness and if you walked around and such you would lose too much blood. But in theory, would you be able to function?

2007-12-20 14:04:24 · 12 answers · asked by Devin M 2 in Biology

Three days after my grandmother died, her handgun went missing. One of our family members accused my Dad of taking it. My mother and I are very good at using divination to find answers to mysteries. We both did separate readings and we both found that the same four people were involved in taking the gun. If you use a divination method, would you mind giving it a shot to see whom you come up with? The main reason I ask is to get confirmation from other divinators.

We found that there was:
a) the person who wanted it stolen
b) the person who came up with the plan that was used to steal it
c) the person who actually stole it
d) the person who has it now

Here are the suspects (names changed to protect the non-innocent):
Mom
Dad
Uncle Al
Uncle Jerry
Aunt Cindy
Cousin April
Cousin Jeremy
Cousin Molly
Cousin Dennis
Cousin Clint
Little Pete
Little Sally
Neighbor Sherry

Please tell what form of divination you used and if you found less or more perpetrators than we did.

2007-12-20 14:02:09 · 8 answers · asked by Tea 6 in Other - Alternative

when something becomes hydrated. what happens to the molecules?

say u hydrated copper(II) sulfate
do the water molecules become part of the copper sulfate molecules? or what?

it says in a book that

"hydrated salts aren't really different from regular salts, since the water isn't actually a part of the core molecule. It's just a regular salt molecule with a water molecule "stuck" to it that just sort of tags along."

so whats the water molecule doing? and how is it "stuck" to the core molecule ?

2007-12-20 14:00:02 · 3 answers · asked by Anonymous in Chemistry

y=2x+5
3x-y=4

3x+2y=71
y=4+2x

y=3x+8
x=y

x-7y=13
3x-5y=23

2007-12-20 13:59:07 · 8 answers · asked by Anonymous in Mathematics

I have seen it being used for making fruit jellies. I'd like to know its other uses.

2007-12-20 13:56:16 · 12 answers · asked by Nithya 2 in Botany

2007-12-20 13:54:32 · 4 answers · asked by Anonymous in Other - Science

Thats what they gave me today when I got my wisdom teeth out and I have never heard of it, but because I am a minor they wanted to try me on this instead of hydro's but could someone please tell me a little bit about it?

2007-12-20 13:43:42 · 5 answers · asked by Anonymous in Medicine

2007-12-20 13:39:53 · 6 answers · asked by Sarah T 3 in Other - Science

2007-12-20 13:37:05 · 3 answers · asked by Anonymous in Geography

Also, what is einstein's general theory of relativity and how does it account for the blackness of black holes?

2007-12-20 13:36:57 · 4 answers · asked by Anonymous in Physics

2007-12-20 13:29:13 · 22 answers · asked by Anonymous in Astronomy & Space

2007-12-20 13:26:16 · 4 answers · asked by tattooedwilla 2 in Geography

2007-12-20 13:25:42 · 5 answers · asked by stonerosedesigndotcom 3 in Other - Science

I need to know how this book relates to chemistry.

thanks (:

2007-12-20 13:25:04 · 6 answers · asked by meee 1 in Biology

Pretend you have a rod, hung from an axis at one of its ends like this.

0-------------------------------

The rod rotates from this horizontal position.

Determine the angular velocity of the rod, as a function of (theta) (theta is the angle through which the rod has swung.)

Please show steps and add details, thank you.

2007-12-20 13:24:59 · 1 answers · asked by Anonymous in Physics

I just want to know where the point is that I could not get any further away from Midland, Michigan, USA.. or if there's a calculator or equation out there that will tell you from any two points where the furthest place on planet earth is from that point..

2007-12-20 13:23:40 · 4 answers · asked by khalidkadrie 1 in Geography

given the density of concentrated sulfuric acid as 2.21g/ml.

2007-12-20 13:23:30 · 3 answers · asked by yeshila 1 in Chemistry

2007-12-20 13:21:47 · 1 answers · asked by Evegotanswers 4 in Biology

HW

2007-12-20 13:12:06 · 3 answers · asked by hussbus444 2 in Earth Sciences & Geology