Physics - September 2007

accel of gravity is 9.8m/s^2

what is the magnitufe of the acceleration of the elevator?

What is its direction?

2007-09-24 06:05:42 · 3 answers · asked by michael 1

i need proper scientific answer.

2007-09-24 05:56:55 · 2 answers · asked by Haider 1

Determine the stopping distances for an automobile with an initial speed of 95 km/h and human reaction time of 3.0 s for the following accelerations.
(a) a = -4.0 m/s2
(b) a = -8.0 m/s2

2007-09-24 05:50:32 · 2 answers · asked by hahahahahaha 1

Rocket has dry weight 10,000 lb and contains 40,000 lb of fuel in tanks. After ignition the motor burns fuel at constant rate and provides constant force of thrust.

The rocket is launched in vertical direction and continues to acclerate in vertical direction.
Intial accleration of the rocket as it lifts off the launch platform is 0.5g.
[ignore air resiatance]

2007-09-24 05:20:46 · 2 answers · asked by Alexander 6

2007-09-24 05:18:26 · 4 answers · asked by bio_addict 1

8 In Figure 22-30, particle 1 of charge q1 = –5.00q and particle 2 of charge q2 = +2.00q are fixed to an x axis. (a) As a multiple of distance L, at what coordinate on the axis is the net electric field of the particles zero? (b) Sketch the net electric field lines.
Fig. 22-30 Problem 8.
http://lowellphysics.org/beta/resources/CH22/Problems/c22x22_11.xform.html

2007-09-24 05:11:15 · 2 answers · asked by dark88 1

The determined Wile E. Coyote is out once more to try to capture the elusive roadrunner. The coyote wears a new pair of Acme power roller skates, which provide a constant horizontal acceleration of 10 m/s2. The coyote starts off at rest 60 m from the edge of a cliff at the instant the roadrunner zips by in the direction of the cliff.

a. If the roadrunner moves with constant speed, find the minimum speed the roadrunner must have in order to reach the cliff before the coyote.

b. If the cliff is 150 m above the base of a canyon, find where the coyote lands in the canyon. (Assume that his skates are still in operation when he is in "flight" and that his horizontal component of acceleration remains constant at 15 m/s2.)

2007-09-24 05:04:07 · 2 answers · asked by Anonymous

A rocket is launched at an angle of 55.0° above the horizontal with an initial speed of 98 m/s. The rocket moves for 3.00 s along its initial line of motion with an acceleration of 30.0 m/s2. At this time, its engines fail and the rocket proceeds to move as a projectile.

(a) Find the maximum altitude reached by the rocket.
m
(b) Find its total time of flight.
s
(c) Find its horizontal range.
m

2007-09-24 04:09:58 · 3 answers · asked by Foxychick 1

An airplane flies 200 km due west from city A to city B and then 300 km in the direction of 32.5° north of west from city B to city C.

(a) In straight-line distance, how far is city C from city A?
( km)

(b) Relative to city A, in what direction is city C?
(° north of west)

2007-09-24 04:05:17 · 2 answers · asked by Foxychick 1

Vector A has a magnitude of 9.60 units and makes an angle of 49.0° counter-clockwise from the positive x-axis. Vector B has a magnitude of 8.00 units and is directed along the negative x-axis.

(a) Using graphical methods, find the vector sum A + B.

*Magnitude of A + B: units

*Direction of A + B: ° counterclockwise from +x-axis

(b) Using graphical methods, find the vector difference A - B.

*Magnitude of A - B: units

*Direction of A - B: ° counterclockwise from +x-axis

2007-09-24 04:03:36 · 2 answers · asked by Foxychick 1

I'm Looking for advice on which speed sensor I should use to measure a small cart. the cart is hardly bigger than a human hand.

2007-09-24 03:57:28 · 2 answers · asked by Anonymous

A lightning bug flies at a velocity of 0.25 m/s due east toward another lightning bug seen off in the distance. A light easterly breeze blows on the bug at a velocity of 0.25 m/s. What is the resultant velocity of the lightning bug?

2007-09-24 03:51:46 · 2 answers · asked by Ayy Girl! 1

a jetliner can fly 6.5 hours on a full load of fuel. Without any wind, it flies at a speed of 2.10 x 10^2 m/s. the plane is to make a round-trip by heading due west for a certain distance, turning around, and then heading due east for the return trip. during the whole flight, the plane encounter 55.0 m/s wind from the jet stream, which blows from west to east. what is the maximum distance that the plane can travel due west and just be able to return home?





A swimmer, capable of swimming at a speed of 1.3 m/s in still water (the swimmer can swim with a speed of 1.3 m/s relative to the water) starts to swim directly across a 2.2 km wide river. However the current is 0.91 m/s and it carries the swimmer downstream


a) how long does it take the swimmer to cross the river?


b) how far downstream will the swimmer be upon reaching the other side of the river?

2007-09-24 03:46:06 · 1 answers · asked by Anonymous

2007-09-24 03:29:56 · 9 answers · asked by Anonymous

2007-09-24 03:28:22 · 7 answers · asked by Anonymous

2007-09-24 03:28:15 · 3 answers · asked by tracey j 1

If our distance from a light-radiating body, that (like a distant star) is nearly a point source, is doubled, the intensity of light received from it becomes (nearly exactly) one quarter of what it was before.
Suppose that it was possible for a star to be stretched across space in a thin incandescent filament that, for all intents and purposes, was endless.
What kind of mathematical law would then relate the intensity of light reaching us from this filament to our distance from it?

2007-09-24 02:41:55 · 5 answers · asked by Anonymous

please put the whole solution. it it a physics problem Newton's Universal law of gravitation. the given formula is Fg=GM1M2/r^2, please include all convertions. thank you

2007-09-24 01:51:43 · 1 answers · asked by Romeo Alexis 1

2007-09-24 01:27:55 · 8 answers · asked by lalaearth 2

This is something I've been pondering over for years!
Is it possible to magnetize a steel ball, say a 1/2" diameter ball-bearing, so that all the 'North' poles act outwards from the surface and all the 'South' poles act inwards towards the center ? And if it could be done, would it act like a magnetic monopole ? What would it do, how would it behave in the presence of other magnetic fields ?

2007-09-24 01:01:53 · 4 answers · asked by Timbo 3

2007-09-24 00:51:52 · 0 answers · asked by Anonymous

2007-09-24 00:00:48 · 11 answers · asked by Neeraj P 1

The best leaper in the animal kingdom is the puma, which can jump to a height of 4 m when leaving the ground at an angle of 45 degrees.
a) with what speed must the puma leave the ground to reach that height?
b) How far does the puma jump horizontally?

for part a I got 12.62 for the speed.

I am not sure how to solve part b...what equation should I be using? and is the acceleration supposed to be zero for the x component? thank you

2007-09-23 23:51:36 · 2 answers · asked by redblitz528 1

what i mean is that how is the gavity (pull) force ,generated at the centre of the earth.

2007-09-23 22:45:29 · 4 answers · asked by kiragu r 1

2007-09-23 21:29:30 · 10 answers · asked by Anonymous

Now no super maths here.
Just Define energy..
And what it is made of...

2007-09-23 21:19:30 · 11 answers · asked by Anonymous

If you are in a spaceship that is traveling at the speed of light, and you turn on the headlights, does anything happen?

2007-09-23 17:55:14 · 5 answers · asked by Anonymous

I am writing an informative 6-8 min speech on string theory. I am not going to get too in depth; just use basic analogies. I wanted to show the benifits of using strings to marry quantum physics and general relativity. All I was going to do is show that if the fundamental building blocks are particles then they would be like dice. I would then display some dice, rolling them, etc. Then I would say that quantum space is like many, many dice- probablity rules here, making things not so easy to predict. I heard on a documentary that the strings in string theory "calm" this quantum froth. So I was going to use rubber bands to show that the dice, instead of being treated as seperate entities, could be treated as sets of probabilty equations, which are interpretated as strings. It is easier to understand this quantum froth (the calming) by looking at it as a multitude a strings. By this slight "calming" of the equations, quantum physics and general relativity are married.

2007-09-23 17:25:33 · 2 answers · asked by pyrojelli 2

A model rocket is fired vertically from rest. It has a net acceleration of 17.5 m/s^2. After 1.5s, its fuel is exhausted and its only acceleration is that due to gravity. The rocket has a mass of 87g and you may assume the mass of the fuel to be much less than 87g. What was the net force on the rocket during the first 1.5 s after liftoff? What force was exerted on the rocket by the burning fuel? What was the net force on the rocket after its fuel was spent? The rocket's vertical velocity was zero instantaneously when it was at the top of its trajectory. What were the net force and acceleration on the rocket at this instant?

2007-09-23 17:13:49 · 2 answers · asked by Shawn 1

The atoms of a solid possess a certain minimum 0 point energy even at 0K, while no such restrictions hold for the molecules of an ideal gas. How does the Uncertainty Principle explain these statements?

2007-09-23 16:15:36 · 1 answers · asked by Mike M 2