Physics - August 2007

Please answer it comprehensively with proofs, please.. Thank you!

2007-08-24 12:08:57 · 19 answers · asked by Anonymous

(the projectile is increased in the same proportion)
(ignore air resistance)

2007-08-24 11:45:31 · 2 answers · asked by Alexander 6

2007-08-24 11:29:59 · 6 answers · asked by jannie 1

http://answers.yahoo.com/question/index;_ylt=Ap3mDd93By3wzuxSsf1OsHXsy6IX?qid=20070824100758AATnYe3

2007-08-24 10:23:45 · 2 answers · asked by balaji.k 2

Why not faster and why not slower? Why at a constant speed? Why so fast? What causes it to travel at the speed of light?

2007-08-24 10:03:22 · 9 answers · asked by Agent Fox 6

The position vector of a fleet footed African cheetah is given by the following funcion of time: x(t)=4.0m-(2m/s)t-(3m/s^2)t^2

a) what is the position vector of the cheetah at the instant the stopwatch commences, t=0s?
b) what is the position vector of the cheetah when the stopwatch indicates t=3s?
c)what is the change in position vector during the three seconds interval between these time instants?

2007-08-24 09:33:48 · 3 answers · asked by mai t 1

If you are travelling at the speed of light in a car, and you switch on your headlights - would you see the beam?

2007-08-24 09:17:44 · 20 answers · asked by Anonymous

2007-08-24 09:06:08 · 3 answers · asked by luvergurl 1

In cloud chambers one can clearly see the beginning and direction/end of a path of an entering alpha particle. Why would this not appear simultaneous to the eye ? Is the particle being slowed by the collision with the vapor within a meter ? If the cloud chamber woud be much larger, would it come to halt ?
(Thanks, from a physics neophyte)

2007-08-24 09:04:06 · 2 answers · asked by hallitubevolunteer1 3

2007-08-24 09:03:08 · 7 answers · asked by Anonymous

Please can you explain the concept of precession. Why do protons in a magnetic field that are 'off balance' start to precess?

Are the protons in my body precessing right now?

2007-08-24 08:37:47 · 2 answers · asked by ? 3

Passes through it , and emerges on the other side at a speed of 210m/s. If the board is 4.00cm thick, how long does the bullet take to pass through it?

2007-08-24 08:37:09 · 4 answers · asked by Pascal 4

If I put my finger on the wall, do you really think Im making contact with the wall, Or is there a gap between the wall and my finger, and the feel of the wall is just an illusion?

2007-08-24 08:04:56 · 23 answers · asked by Anonymous

Place another quarter flat on the surface of the desk, press its edge against the edge of the first quarter, and start roll it with a finger around the first quarter without skidding of their edges.

If the center of second quarter completes one revolution in 3 seconds, what is angualar velocity of this qurter with respect to the desk?

2007-08-24 07:09:16 · 6 answers · asked by Alexander 6

A boy runs at speed 5m/s counter-clockwise on the rim of carousel (with respect to the carousel).

a) What is direction and magtidue of coriolis force acting on the boy?
b) What is angle (and direction) of inclination of the boy to the vertical?

2007-08-24 06:42:10 · 2 answers · asked by Alexander 6

In the chapter where he discusses singularity, and the "big bang" -- just what "God" is he referring to loosely, in the first chapter? What context is he using it in? It just surprises me that a man of science, particularly, Hawking would use that word...

"One can imagine that God created the universe at the instant of the big bang" p. 9, Ch. 1

2007-08-24 06:31:36 · 10 answers · asked by Anonymous

2007-08-24 06:13:36 · 6 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 06:07:58 · 3 answers · asked by balaji.k 2

Is it moving in the positive or negative direction of x just then?

2007-08-24 05:26:33 · 2 answers · asked by Wonder 2

I don't know how. I thought of increasing the positive charge in a very high and elevated area.

What do you think? Is that possible?

2007-08-24 05:11:56 · 7 answers · asked by Anonymous

2007-08-24 05:09:03 · 1 answers · asked by Anonymous

2007-08-24 05:00:27 · 7 answers · asked by stevenyoungers 1

The projectile was fired from (90W, 0N) and landed on the opposite side of the Earth at (90E, 0E).

Curious amateur photographer located at (0E, 30N) noticed a bright object rising over the horizon, and made a picture of its trajectory.
He directed his camera horizotally due south, and let exposition continue until the object fell under horizon. The trace of the projectile on the film is

a) parabola
b) ellipse
c) hyperbola
d) impossible to predict


(ignore rotation of Earth)

2007-08-24 04:59:23 · 1 answers · asked by Alexander 6

please explain

2007-08-24 04:17:16 · 4 answers · asked by Grand Phuba 5

If a passenger train departs station x traveling at light speed and another train leaving station y at 1 mile an hour, at what point will they collide? (you many use your calculator for this problem)

2007-08-24 04:17:15 · 3 answers · asked by reido_sakaiya 1

the question:

the current in a 3.5H(henry) inducator increses uniformly from zero to 50 mA in 500 ms.
determine the e.m.f.,and the stored energy at the end of this time?

help i have no clue =| and thats all ive been given
cheers

2007-08-24 03:59:16 · 2 answers · asked by london lad 1

I am absolutely stumped regarding this questions. Could someone please assist me? I would be extremely grateful.

A runner is jogging at a steady v = 8.4 km/hr. When the runner is L = 4.9 km from the finish line, a bird begins flying from the runner to the finish line at V = 16.8 km/hr (2 times as fast as the runner). When the bird reaches the finish line, it turns around and flies back to the runner. We will assume that the bird occupies only one point in space, ie., a zero length bird.

How far does the bird travel? Answer in units of km.

ALSO:

After this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. The bird repeats the back and forth trips until the runner reaches the finish line.

How far does the bird travel from the beginning? (ie include the distance traveled to the first encounter) Answer in units of km.

2007-08-24 03:54:04 · 3 answers · asked by sg88 1

Is there a similar law like the Law of Boyle (Robert Boyle 1661) that works for fluids?
I would like to know if the temperature of water increases if I increase the pressure from 1 atm to 10 atm. e.g.

2007-08-24 03:44:15 · 2 answers · asked by Greek Oracle 4

What is your average velocity?

2007-08-24 03:28:00 · 3 answers · asked by Wonder 2

Might teleportation achieve this, for example?

2007-08-24 03:06:08 · 11 answers · asked by Buzzard 7