Physics - July 2007

okay, i know poeple sometimes say the moon makes poeple crazy or a lunatic. by science its true but by observation its not.

or

the moon looks bigger when next to the earths horizon but in the sky it looks smaller. science says it never shrank but by observation it did.

any help?

2007-07-09 08:53:20 · 5 answers · asked by adam s 2

What form of transportation converts the the highest percent of energy input (whether it is gas or electricity or calories) into forward locomotion of the final object being moved?

For example, it cannot be a car, since even the most efficient car has to move over a ton of metal in order to transport a 185 person.

I seem to recall reading the a bicycle was the most efficient but wonder if it is true.

2007-07-09 08:46:52 · 5 answers · asked by A Baby Ate My Dingo 4

2007-07-09 08:45:19 · 5 answers · asked by aRe_yeS 2

You and your friend run around a racetrack at constant speed but you are faster than your friend. While you complete a lap in time T1, your friend completes it in a longer time T2. Suppose that at time t=0 the two of you are abreast and that you are just about to overtake him. Suppose further that the next time you pass him he has run n full laps. Prove that your passing frequency f, i.e. the number of times per second that you pass him is given by (T2-T1)/(T1*T2).

2007-07-09 08:27:50 · 2 answers · asked by Anonymous

http://upload.wikimedia.org/wikipedia/commons/e/ea/BB61_USS_Iowa_BB61_broadside_USN.jpg

The batleship is made mostly of steel.

2007-07-09 08:12:32 · 10 answers · asked by Alexander 6

the cat was dead and not dead at the same time??? how???
how did they do that???

2007-07-09 08:00:46 · 6 answers · asked by Phatcat 2

If you do can you offer me some guidance. Can you answer some typical and not so typical questions for me. I'm at a stand still in my life and I need some answers. This is serious beyond my profile as a real person asking real questions not as a gnome. please help me.

2007-07-09 07:53:17 · 6 answers · asked by Anonymous

2007-07-09 07:47:38 · 2 answers · asked by Alexander 6

For example in 1D space (and only in 1D) phase
transitions do not exist

2007-07-09 07:19:29 · 5 answers · asked by Alexander 6

Submarine goes at speed c/2 in liquid
with refraction index n=2.

What heppens if headligths are turned on?

2007-07-09 07:15:57 · 5 answers · asked by Alexander 6

There are two stars A and B in two remote galaxies.
We measured angle S between these stars in
the sky, and asked their hypothetical inghabitants
to do the same, ie angles between A&S from B,
and B&S from A. Is the sum of angles
A + B + S greater, equal to, or smaller than π?

2007-07-09 07:11:51 · 4 answers · asked by Alexander 6

it will take 42 minutes to travel to the other side,
if the conveyance is allowed to free fall.

This energy-effective method of transportation
has the disadvantage that passengers will remain
in weightlessness for prolonged period of time,
and may feel uncomfortable.

If we want the passengers to feel normal weight
during the travel, and minimize travel time,

how much time will the trip take in that case?

Our teacher gave up on us already,
all he wants is a just number.

2007-07-09 07:05:58 · 7 answers · asked by Alexander 6

The sun rises at due East.

What is the ratio of brightnesses of sky in zenith
and near horizon due South immediately after
sunrise?

2007-07-09 07:03:38 · 5 answers · asked by Alexander 6

How big was the universe (and in how many dimensions) before the big bang?
If I dug a hole in the earth and drove into it at the speed of light, would my headlights shine all the way through?
Could I have traveled back in time to fake the moon landings?
If the earth stopped spinning because of a black hole, would we notice (since my cousin's trashman said there's no such thing as centrifugal force), and would that turn off gravity and change the color of the sky?

2007-07-09 06:59:39 · 11 answers · asked by Anonymous

"Thats just the tip of the iceberg" is a popular expression. It means that what you see is only part of the overall problem. if most of an iceberg is out of sight below the water level what is the most likely dinsity of the ice berg? (assume a density of 1.03 g/mL for seawater)

a) 0.88 g/cc
b) 1.23 g/cc
c) 0.23 g/cc
d) 4.14 g/cc

[Pick the correct answer!!]-Answer Correctly!!

2007-07-09 06:56:28 · 7 answers · asked by Anonymous

2007-07-09 06:42:03 · 12 answers · asked by Anonymous

a) It has a large mass
b) It has a large volume
c) It has high density
d) It has low density

[Pick on e of the above]-Answer Correctly!!!

2007-07-09 06:38:16 · 8 answers · asked by Anonymous

If you shot a laser pointer into space would the light from the beam make any sound and if so how could you hear it?

2007-07-09 06:37:29 · 7 answers · asked by Anonymous

Consider the 100% efficient hydraulic system below used to lift a boat: (no pic)


If the boat weighs 1600 N and must be lifted 0.8 meter (dout), how far down (din) must the input piston be pushed using a force of 500 N ?

2007-07-09 06:27:20 · 2 answers · asked by Anonymous

A coasting cart has velocities 1.5 m/s, 4 m/s and 11.75 m/s at clock times t = 0 s, 3 s and 6 s. Approximately how far does it move and at what average rate does it accelerate over each of the two time intervals (i.e., 0- 3 seconds and 3 - 6 seconds)?

If the automobile is coasting, and if air resistance is not a significant factor, then over which time interval do you think the average slope of the road is greatest?

2007-07-09 06:13:13 · 2 answers · asked by benzene boy 1

2007-07-09 06:04:42 · 7 answers · asked by ? 5

2007-07-09 06:01:16 · 5 answers · asked by Anonymous

2007-07-09 05:47:54 · 5 answers · asked by larry r 1

2007-07-09 05:36:01 · 8 answers · asked by Zefram 2

2007-07-09 05:22:17 · 11 answers · asked by Anonymous

A brick is lifted to a given height and then dropped to the ground. Next, a second brick, which weighs twiceas much as the first, is lifted just as high as the first and then it too is dropped to the ground. When the second brick strikes the ground it has:

a) half as much kinectic energy
b) as much kinectic energy as the first
c) twice as much kinectic energy as the first
d) four times as much kinectic energy as the first

As always, decide on only one answer. A correct answer accompanied by a correct explanation beats a correct answer by itself.

I believe that I already know the answer (please don't let me be wrong!) to the question. I offer this question for the challenge of solving it as well as for the educational value.

If you don't like the question (for whatever reason) just move on to another. There are pleanty more!

Onwards to glory (and points!)

2007-07-09 05:02:53 · 9 answers · asked by ? 6

Does anybody know a simplified version of the Kubelka-Munk model on optics? And if there are any sources that they could lead me to?

2007-07-09 04:46:29 · 1 answers · asked by Anonymous

http://www.youtube.com/watch?v=lghIDQSbxw8

2007-07-09 03:22:38 · 2 answers · asked by Yahoo! 5

Suppose I were in a minor accident. I was standing still weighing 50 kg. The vehicle weighed 500kg and was only going at 5 kph...

Would an elephant weighing 5000 kg need to be hit by a 50000 kg weight travelling 5 kph in order to feel what I felt? Or do I need to scale up the speed too?

(Disclaimer: despite my choice of phrasing, no elephants shall be hurt by gigantic weights in the making or answering of this question :P )

2007-07-09 03:11:23 · 4 answers · asked by mirhalves 1

Need to know what it is (concept + formula) and what its uses are?

2007-07-09 03:07:06 · 3 answers · asked by Anonymous