Physics - June 2007

Doesn't it have serious problems in some or all of the following areas : testability, the virtual infinity of Universes that inhabit the string theory landscape, the paradoxical background dependence, the excessively difficult mathematics, the absence of a guiding principle such as the Uncertainty principle or the Principle of Equivalence and it's heavy use of highly abstract maths to explain its key features eg. p-branes, supersymmetry, curled-up dimensions, holography,dualities,... amid a dearth of experimental support.Finally, isn't it the case that other contenders notably Loop Quantum Gravity have to progress in it's shadow? Even if only some of this is true isn't it quite unsatisfactory? A bit like the 21st century version of the ether...Apparently for the experts in the field it's beautiful but does that make it true?

2007-06-14 06:08:25 · 5 answers · asked by Maxim 2

2007-06-14 05:57:15 · 6 answers · asked by Anonymous

Do you know the answer for this? A body thrown vertically upwards reaches a maximum height 'h' and then returns to the ground. Calculate the displacement and distance.

2007-06-14 05:54:42 · 4 answers · asked by Anonymous

Only scientificor physical anwers pls.
Thank you so much

2007-06-14 05:49:56 · 3 answers · asked by Anonymous

why do the blues scatter and not stay till the end

2007-06-14 05:22:01 · 5 answers · asked by wants all the answers 1

2007-06-14 05:16:52 · 12 answers · asked by wants all the answers 1

2007-06-14 05:15:07 · 3 answers · asked by john c 1

The universe was created by the big bang theory. The small singularity that just exploded to create the universe.. How did it create the universe, What space was it in before the Big bang .If the universe is expanding then what is it expanding in.Can you liken the universe as per a circle. No beginning therefore no end?

2007-06-14 04:59:31 · 22 answers · asked by I B 1

Since we can hear sounds around the corner of a hallway, we know that sound waves can move in ways that permit you to hear sounds that are not in a direct pathway from the source to your ears, What property of waves allows this?
A.reflection
B.refraction
C.diffraction
D.echolation

2007-06-14 04:53:37 · 3 answers · asked by Anonymous

A,collide with the outside air and do work on the air outside.
B.cause the pistions to move outward as they condense in the cylinder.
C.absorb heat from the outside gases.
D.decrease the entropy of the outside air

2007-06-14 04:49:07 · 2 answers · asked by Anonymous

A 76.0ohm & a 48.0ohm resistor are connected in parallel. When this combination is connected across a battery, the current delivered by the battery is 0.350A. When the 48.0ohm is resistor is disconnected, the current from the battery drops to 0.200A. Determine the emf of the battery.

2) Two cylindrical rods, one copper & the other iron, are identical in lengths and cross-sectional areas. They are joined, end-to-end, to form one long rod. A 30V battery is connected across the free ends of the copper-iron rod. What is the voltage between the ends of the copper rod?

2007-06-14 04:21:30 · 3 answers · asked by Brandy J 1

To find the launch angle when fireing water ballons (250g) for 30 meters away on the same plan. We where allowed to shoot two vertical shoots and we had the following results.Full catalpult extend 2.10m, the ballon took 4.3 seconds to hit the ground.Please can someone tell me how I need to work it out and to transfer all formulas onto excel.
Thanks

2007-06-14 04:18:48 · 1 answers · asked by Jack 1

1) A 15.16ohm coffee maker & a 16.50ohm frying pan are connected in series across a 120V source of voltage. A 22.21ohm bread maker is also connected across the 120V source & is in parallel w/the series combination. Find the total current supplied by the source of voltage.

2) A 64.0ohm resistor is connected in parallel w/a 112ohm resistor. This parallel group is connected in series with a 18.0ohm resistor. The total combination is connected across a 12V battery. (a) find the current and (b) the power dissipated in the 112ohm resistor.

3) A new "D" battery has an emf of 1.50V. When a wire of negligible resistance is connected between the terminals of the battery, a current of 27.8A is produced. Calculate the internal resistance of the battery.

4) Three capacitors (4.13, 6.01, & 12.5microF) are connected in series across a 57.0V battery. Calculate the voltage across the 4.13microF capacitor.

2007-06-14 04:17:37 · 2 answers · asked by Brandy J 1

What happens when light passes through matter?

2007-06-14 03:57:08 · 14 answers · asked by Sam 3

2007-06-14 03:39:06 · 21 answers · asked by Hermione 2

the options are:
A: double
B: half
C: 8 times
D: 1/8 times

2007-06-14 03:33:57 · 5 answers · asked by Swathi M 1

2007-06-14 03:29:51 · 7 answers · asked by Anonymous

You can either comment on the movie or try to assert something as absolutely true.

For example Einstein proved that while Newton's Laws of Thermodynamics were useful they weren't absolutely true. Before relativity, Newtons Laws were considered absolute and the bedrock of the hard sciences.

Now quantum physics comes along and blows the doors off everything we once thought to be true (well at least for some people's understanding of it).

String theory is so far out there that we can't even develop an apparatus to test it.

Whatever you may think don't forget that Einstein's theory of relativity was considered pure fantasy by the scientific elite at the time he came up with it. It took a very long time for the scientific community to catch up with him and accept his ideas and for society to regard him as a genius.

2007-06-14 03:17:25 · 9 answers · asked by megalomaniac 7

for example if you hold a wishbone and want to break it. How do I break it to split it exactly half? this is a physics question.. can I equal the force in both of my hands to split the bone exactly half or is there something in physics that contradicts it?

2007-06-14 03:16:02 · 7 answers · asked by d_man 1

what would happen to a rocket if it ran out of fuel while it was still in space?
would it crash into a nearby planet but would it kinda float around space because there is no friction in space, or would it orbit around a planet or something?..

just wondering

2007-06-14 03:02:27 · 8 answers · asked by kiwi 2

2007-06-14 02:33:01 · 6 answers · asked by jeree 1

2007-06-14 02:29:39 · 4 answers · asked by jeree 1

2007-06-14 02:27:46 · 14 answers · asked by Anonymous

in experiments in our labratory ,our professor told us to do this ,but didnt explained the reason,instead he asked us to bring him its reason.really why?!

2007-06-14 02:19:04 · 5 answers · asked by david 1

I have been experimenting with a hydrogel substance of nonsoluble polymers in a semi solid state, trying to achieve a cooling effect or freezing effect of the gel without having to refrigerate. Is there an alternative way, like by applying direct electricity on the gel or otherwise?

2007-06-14 02:17:45 · 4 answers · asked by donald k 1

A cat leaps horizontally from a flat roof 7.5 m above the ground and lands on another flat roof 5 m above the ground and 3.5 m away horizontally.

how long in seconds does the leap take?

2007-06-14 01:45:38 · 3 answers · asked by Anonymous

of 2cm and then the block is released from rest.(A)Cal the speed of the block as it passes through the equlibrium if a constant frictionless force of 4N retards the motion? (B)Find the speed of the block if it pass through the equilibrium for a frictionless surface ? (C) Cal the change in kinetic energy of the block ?

2007-06-14 01:19:38 · 1 answers · asked by Anonymous

2007-06-14 01:18:40 · 7 answers · asked by b-an 1

Your Defination of Blackbody

2007-06-14 01:08:17 · 2 answers · asked by Anonymous

You might be aware that aeroplane was an impossible device, but mankind made it.
Live telecast is also a surprising system.
But Hindu ancient texts already refer such devices Pushpak Viman and Dhutrastra-Sanjay Live commentary of Mahabharat war,..and Sudarsan Chakra on the hand of God and Godess....Now, the question is, Is it possible to make a self rotating device producing energy just like a 'sudarshan chakra' ?
If I say we can make it, which rest of world refute by their scientific superstition and believes such thing is impossible. I have confirmed that no Indian Institute of Technology or Science is undertaking any research on this subject. I want to know is there any body to sponcer research and making of proto-type for which design is ready? I hope the reader of this question will reply his opinion or ask persons in his/her group to solve the problem of searching a new source of energy.--GRAVITY(GAYATRI)...No cost , constant, available everywhere on earth. Pl. read again

2007-06-14 00:44:08 · 6 answers · asked by paresh 1