Physics - August 2007

Now Imagine theres a point 'A' vertically above the surface of earth. the distance of point A from the horizontal plane is given by X metres .also, imagine theres no atmosphere.

Now Imagine from within that point A , a chain {made of identical oval shaped rings linked sequentially} keeps on appearing {materializing}

and it starts to fall down due to gravity and hits the ground.the liks which appear from within point A are static and are pulled down by the links below them i.e., the faster you pull the faster the new links materialize. now what will be the velocity of the chain { particularly the rings} when they hit the ground if X = 20 metres .(remember the chain keeps on materializing from the point A}.

i think the terminalvelocity of the chain can be given by Vt = squarerootof (Xg)

where g = acceleration due to gravity(take g= 10 m/s^2).
now sqrroot of(20*10) = 14.14.so , here Vt = 14.14.

2007-08-25 05:07:55 · 3 answers · asked by balaji.k 2

a block of mass 2 kg is kept on a rough inclined plane of inclination 30 fixed in an elevator. the elevator starts to come down with an acceleration of 2ms and block remains at rest on the incline. whate is the work done by the normal force acting on the block in 4 second
answer 96 j

2007-08-25 05:04:44 · 3 answers · asked by sameerteacher01 1

my question is do u agree with my teacher. If so explain your reasoning and explain why you think that.

whoever gives most reasons and gives best insightful deatails to support will receive the "Best Answer."

10-15 sentences minimum please

2007-08-25 04:40:43 · 4 answers · asked by Anonymous

1. A stone is thrown horizontally at a speed of 5m/s from the top of a cliff 78.4m high.

a) How long does it take the stone to rech the bottom of the cliff?

b)How far from the base of the cliff does the stone strike the ground?

c) What are the horizontal and vertical components of the velocity of the stone as it hits the ground?

d) What is the final speed of the stone as it hits the ground?
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2. How would the answers to a,b,and c change:

a) If the stone were thrown with twice the horizontal speed? (Explain)

b) If the stone were thrown with the same speed but the cliff were twice as high? (Explain)

2007-08-25 02:42:31 · 4 answers · asked by boy101 3

How hot is a / an :
Sun's Core
Animal that's hibernating
Refrigerator
Match Stick that just light up

And how did they measure it??

2007-08-25 02:01:00 · 2 answers · asked by Kenny 1

we arestudying compressibility with different states of matter so.....

Explain why AIR is used to inflate tyres...
and
Explain why STEEL is used to make railways..

i need "science like" answers...

PLEASE HELP THANKS!

2007-08-25 01:51:57 · 4 answers · asked by Anonymous

Now Imagine theres a point 'A' vertically above the surface of earth. the distance of point A from the horizontal plane is given by X metres .also, imagine theres no atmosphere.

Now Imagine from within that point A , a chain {made of identical oval shaped rings linked sequentially} keeps on appearing {materializing}

and it starts to fall down due to gravity and hits the ground.the liks which appear from within point A are static and are pulled down by the links below them i.e., the faster you pull the faster the new links materialize. now what will be the velocity of the chain { particularly the rings} when they hit the ground if X = 20 metres .(remember the chain keeps on materializing from the point A}.

i think the terminalvelocity of the chain can be given by Vt = squarerootof (Xg)

where g = acceleration due to gravity(take g= 10 m/s^2).
now sqrroot of(20*10) = 14.14.so , here Vt = 14.14.

2007-08-25 01:29:44 · 1 answers · asked by balaji.k 2

Hey if u could explain these to me:

1) "Lisa finds that when she increases the voltage across an ohmic resistor from 6 V to 10 V the current increases by 2 A.
What is the resistance of this resistor?"
OK so if u work out the gradient that's 4/2 = 2. The answer gives 2 ohms, but isn't resistence the inverse of the gradient, so it should be 1/2 ??

2) The resistance of a certain piece of wire is found to be 0.8 ohm. What would be the resistance of a piece of wire of twice the diameter?
if it's twice then shouldn't u do 0.8/2 = 0.4? But my book says it's 0.2 ohm.

2007-08-25 01:29:13 · 6 answers · asked by Anonymous

2007-08-25 00:47:50 · 6 answers · asked by April 5

2007-08-25 00:31:15 · 9 answers · asked by silversliver5000 2

I was reading about the term 'absolute zero' and I was wondering if at some point absolute zero and the most extreme temperature of heat meet to be one in the same....meaning that matter and energy cannot exist.

2007-08-24 22:36:09 · 6 answers · asked by bonbebe 2

Is there a particular reason unimorphs only have just one thin piezo disc? Could two or more such piezo discs be used instead of just one to get greater sound output? Can a unimorph be made to produce low ultrasonic frequencies as well?

2007-08-24 22:34:26 · 1 answers · asked by Hunter 6

A molecule in liquid is attracted by molecules from every direction (due to cohesive force)-- so there is no net force on it. But the surface molecules of liquid feel some net downward force coz their position (there is no liquid molecules upward to exert cohesive force).
When something feel a net force it is forced to move to direction of the force. But as we know the surface molecules normally does'nt exchange their position with lower surface molecules---
Now my question is what is the other force that balance the net downward force of surface molecules?
Thx.

2007-08-24 22:11:09 · 5 answers · asked by Anonymous

I think the surface tension is due to the extra attraction among surface molecules.
Who exert the tension force? The surface molecules of course-- so it is nothing but a kind of molecular attraction.

2007-08-24 21:42:57 · 3 answers · asked by Anonymous

imagine theres a horizontal planeA bove which the effects of gravity are not felt. any object above the plane just floats and gravity has no influence on it.
now take a chain(for e.g:made of small steel ring) of length hundred metres above the planeA and arrange it so that its in a heap just above the planeA. but take care the chain is not entangled and should be easy to stretch along its length.

now pull the lower end of the thread below the planeA and the chain runs down like a single thread and hits the ground and as links pull down on the ones they are linked to , the whole length of the chain will run like a thread and hit the ground in some time. now take planeA is 20metres above the ground surface. the terminal velocity of links when they hit ground will be around 14 metres .
now consider hundred metres of the chain weighs 100 units. the potential energy of the chain just above the planeA will be m*g*h =100 *9.8*20
=19600 units.

2007-08-24 20:20:01 · 4 answers · asked by balaji.k 2

2007-08-24 19:45:28 · 15 answers · asked by cookiesmom 7

2007-08-24 19:19:24 · 4 answers · asked by LELAND 4

2007-08-24 17:38:27 · 6 answers · asked by Kurt Orlando Patterson 2

and y does it not discharge when connected through a bulb or anything else.

2007-08-24 17:31:44 · 8 answers · asked by Anonymous

2007-08-24 17:06:04 · 10 answers · asked by antariksh 1

Then how is it that light cannot escape a black hole? Given that the photons are travelling at the maximum velocity attainable, how could a black hole have enough gravitational energy to prevent even light from escaping? Is this not a pardox? If nothing can have a higher energy than a photon moving at the speed of light, how can a black hole put it in?

2007-08-24 16:49:16 · 8 answers · asked by joepatterson37 2

Ive heard that it could be dangerous for your heart because its a lot of pressure.

I just want to clear this out.

2007-08-24 15:45:37 · 6 answers · asked by Adrian 1

ganesh wanted to lift a heavy basket of books to the tree house. he found it difficult to to lift the books using the single fixed pulley. Why is that so?

2007-08-24 15:09:38 · 5 answers · asked by Anonymous

2007-08-24 14:42:32 · 6 answers · asked by CT L 1

What are some chemical and physical properties of it, where is it found, who discovered it and does anyone has a fact about it that i probably dont already know??

2007-08-24 14:08:03 · 4 answers · asked by jay234 2

2007-08-24 14:04:57 · 18 answers · asked by Marvin P 1

Plasma is, in basic terms, the prevalent phase of matter found in stars, right? And it's extremely hot?

Wouldn't it then burn, not only anything that happens to touch it, but also whatever was inside it as well? The temperature of the air within the shield would be very high, it seems.

And don't answer just to tell me that "it's fiction". I'm well aware of that. But science fiction usually has some kind of scientific basis as well.

2007-08-24 13:27:19 · 3 answers · asked by Joshua C 2

2007-08-24 13:01:07 · 5 answers · asked by David L 4

where the pressure is essentially zero?

2007-08-24 12:27:02 · 7 answers · asked by Helen 1

2007-08-24 12:12:33 · 5 answers · asked by Helen 1