Physics - December 2006

The exact physics and calculations to go through.

2006-12-20 23:12:59 · 5 answers · asked by Anonymous

Einstein showed that all frames of reference are equally valid, so the earth can be considered as a frame of reference independent of the rest of the universe. Given that the earth is merely rotating and NOT accelerating, why are winds or missiles or anything above the earth's surface affected by the earth's rotation?

Does it have to do with conservation of angular momentum, as a body travels from large spinning circles toward smaller spinning circles (lines of latitude)? Even then, it still seems contradictory to relativity theory in that the earth doesn't "know" that it is rotating, nor does anything on it.

I guess my question is Why is a rotating frame of reference discernable from a non-rotating one? It's only rotating relative to the rest of the universe; does the universe's inertia matter? Is this related to gyroscopic precession?

I've read the Wikipedia entry and seen the movies of balls on merry-go-rounds. What am I not getting?

This has been bugging me for 15 years

2006-12-20 22:58:43 · 6 answers · asked by warm106fm 1

can someone please explain the theory of "the big bang" and how people have come to that conclusion?

(i'm a christian, so i know how it works in the bible. i dont get the big bang, however...)

2006-12-20 22:27:06 · 4 answers · asked by Anonymous

I like this question. I will continue asking until someone answers correctly.

P.S. The answer is not that they bounce back in opposite directions because reversing course involves a momentary velocity of zero, during which the objects (even if only infinitesimally briefly) are stopped.

2006-12-20 22:21:01 · 15 answers · asked by wwwwwwwfe 1

Please provide a convincing reason.

2006-12-20 22:19:37 · 22 answers · asked by Anonymous

velocity,displacement,thrust????????

2006-12-20 21:43:59 · 6 answers · asked by rahmaan 1

If I were superhuman and could jump to the moon, the earth would definitly rotate whilst up there, so is there a sliding scale? I can't imagine that it is a case of the answer being "No, because I am within the earth's atmosphere" as that would gradually decrease so there can't be a line at which a jump 1m above the earth rotates, and 1m below the earth does not? And if it is a sliding scale, then I imagine the case is that it would rotate at such a low level as not to be noticable, else it is negated by local air resistance?

2006-12-20 21:40:44 · 18 answers · asked by Marky 6

2006-12-20 21:04:50 · 7 answers · asked by Anonymous

If we can ever go back in time, knowing we couldn't change anything, would we go back and investigate the event fromt he inside out? If that were the case people would travel back and be in the towers to be witness to the event. I have heard that many people think there were bombs in and around the towers that helped cuase the devistation. It would be interesting to know if that were true.

2006-12-20 20:05:35 · 7 answers · asked by Anonymous

2006-12-20 19:49:40 · 13 answers · asked by ravi 1

She again turns left and goes 3 km. and turns to her right and starts walking striaght. In which direction is she walking now?

2006-12-20 19:47:32 · 5 answers · asked by raj_paragon 1

2006-12-20 19:46:08 · 6 answers · asked by zeionuttz 1

2006-12-20 19:45:25 · 12 answers · asked by Anonymous

Ok, so I was reading this article today about electromagnetic fields and it gave me a weird idea that leads me to a question. I learned in physics that electric fields and magnetic fields exist perpendicularly to one another as well as inversely in their magnitudes i.e. as one goes down the other goes up......what I inferred from this article was that this inverse magnitude thing is not necessarily always so, which is why complex numbers are useful in calculations involving this stuff....so my question is, what kind of circumstance would make it so there wasn't a direct 1:1 inverse relationship between the two i.e. one of them goes down, but the other doesn't go up as much as it should etc....

2006-12-20 17:48:40 · 3 answers · asked by Anonymous

2006-12-20 15:44:42 · 11 answers · asked by md5079 1

!!! no funnies please !!!

2006-12-20 13:28:11 · 5 answers · asked by josh 2

II don't get this problem. I don't know what the difference is between the ball at the top of its path and when it is at the bottom of its path.

The answer that I got was .000137. I think that is wrong. can someone show and explain to me how I do this?

A ball on the end of a string is cleverly revolved at a uniform rate in a vertical circle of radius 85.0 cm. Its speed is 3.90 m/s and its mass is 0.300 kg.

What is the tension in the string when the ball is at the top of its path? What about when it is at the bottom of its path.

2006-12-20 13:13:17 · 1 answers · asked by beast 1

can anyone please find a cartoon that defies the laws of phisis ( please write a link for a short clip of it) and explain how it defies the laws of physics

note- please dont use dragon ball z, or humans flying


thanks!

2006-12-20 13:02:07 · 4 answers · asked by Valerie 3

2006-12-20 12:35:50 · 11 answers · asked by Chief of sinners 4

When resting, a particular person has a resting metabolic rate of about 3.0 x 105 joules per hour.
The person is submerged neck-deep into a tub containing 1.2 x 103 kg of water at 21.0 °C. If the heat
from the person goes only into the water, find the water temperature after half an hour.

2006-12-20 12:26:54 · 1 answers · asked by ????????????????? 2

At a temperature of 0 °C, the mass and volume of a liquid are 825 kg and 1.17 m3. The coefficient
of volume expansion for the fluid is 1.26 x 10-3 (C°)-1. (a) What is the density of the fluid at this
temperature? (b) What is the density of the fluid when the temperature has risen to 20.0 °C.

2006-12-20 12:25:45 · 2 answers · asked by ????????????????? 2

A car of weight 2720 N operating at a rate of 156 Kw develops a maximum speed of 31 m/s on a level, horizontal road.
Assuming that the resistive force (due to friction and air resistance) remains constant, what is the car's maximum speed on an incline of 1 in 20, i.e. if @ (theta) is the angle of the incline with the horizontal, sin @ = 1/20? Answer in units of m/s

A 172 kg crate is pulled along a level surface by an engine. The coefficient of kinetic friction between the crate and the surface is 0.496. The acceleration of gravity is 9.8 m/s2
How much power must the engine deliver to move the crate at a constant speed of 7.53 m/s? Answer in units of watts.

First correct answerer gets 10 points!

2006-12-20 12:23:36 · 2 answers · asked by evilgenius4930 5

(Part 1)
A dragster and driver together have mass
885.3 kg. The dragster, starting from rest,
attains a speed of 26.9 m/s in 0.58 s.
Find the average acceleration of the drag-
ster during this time interval. Answer in units
of m/s^2.

(Part 2)
What is the size of the average force on the
dragster during this time interval? Answer in
units of N.

(Part 3)
Assume: The driver has a mass of 79 kg.
What horizontal force does the seat exert
on the driver? Answer in units of N.

2006-12-20 12:19:59 · 3 answers · asked by Anonymous

2006-12-20 12:17:55 · 5 answers · asked by beast 1

An elevator starts from rest with a constant
upward acceleration and moves 1m in the first
1.5 s. A passenger in the elevator is holding a
9.2 kg bundle at the end of a vertical cord.
The acceleration of gravity is 9.8 m/s^2.
What is the tension in the cord as the ele-
vator accelerates? Answer in units of N.

2006-12-20 12:17:20 · 2 answers · asked by Anonymous

Why does time slow the closer to a higher gravitational field or if matter is sped up?
Try to explain in general terms, without details into general or special relativity, can use some, what is the correlation between speed and high gravitational field in slowing time?

2006-12-20 12:16:08 · 2 answers · asked by Courageous Capt. Cat 3

2006-12-20 11:55:08 · 6 answers · asked by Rawkus 3

I mean clearer than glass or plexi-glass, that light passes through almost without being bent.

2006-12-20 11:22:13 · 4 answers · asked by henry j 1

angle of reflection = angle of incidence + angle of refraction.

is this always true or only for certain situations?

2006-12-20 11:03:43 · 2 answers · asked by 8 3

each individual bungee chord has an elastic constant fo 200 N/m and is 35 m long.A jumper will use a number of these to safely leap from a bridge which is 45 m above a river. (two chords double K, three triple etc) The jumper is 88 kg and we measure h=0 at the point where the chords snap taut. How many chords does she need if she wants to just touch the surface of the water?

On the back, he wrote the answer as 3 but didn't put an explanation.

I tried all of the equations but couldn't figure it out...HELP!!!

2006-12-20 10:59:39 · 1 answers · asked by Anonymous