Physics - September 2007

please enumerate changes

2007-09-15 01:10:32 · 3 answers · asked by jin11_knight 1

2007-09-14 20:00:10 · 6 answers · asked by Sammers 1

mechanics, properties of matter, Electromagnetics and optics.

2007-09-14 19:34:20 · 6 answers · asked by Anonymous

2007-09-14 19:33:35 · 6 answers · asked by Asker 6

Can anybody tell me what will be the workdone by magnetic field on a positive charge particle?

2007-09-14 19:32:57 · 7 answers · asked by HESHSHAM 1

Liquid Nitrogen is a liquid at 77 deg. Kelvin. To prevent it from warming and expanding to a gaseous state, at what temperature would I have to set a thermostat to keep it cryogenically cooled to 77deg Kelvin. In other words, does it take a lot of energy to keep it at that temperature?

2007-09-14 18:35:42 · 4 answers · asked by delta dawn 4

PHYSICS

2007-09-14 18:15:42 · 8 answers · asked by spict_7271 1

If a wire is hooked up to an Electro Motive Force (EMF) and produces a magnetic field, would it produce the same magnetic field strength if another identical wire was hooked up to the EMF in parralell? Or would the magnetic field be stronger or weaker?

2007-09-14 18:10:24 · 3 answers · asked by Anonymous

the greatest height reported for a jump into an airbag is 99.4 m. Dan Koko jumped from a Vegas hotel and struck the airbag with a speed of 39 m/s. To assess the effects of air resitance determine how fast he would have been traveling on impact if air resistance had been absent.

2007-09-14 17:01:34 · 4 answers · asked by smarin1987 2

does science leave any room for religion now that its discovered theories of relativity, superstring theory, BIG BANG THEORY!, wormholes, blackholes, stars, etc..... why have religioin anymore? everything has chance not luck. everything has reason not a supernatural "thing" controling it. Matter is not created by "god" it is eternal. What is the use of religion when it is so unaccurate to the creation of the universe???

2007-09-14 16:38:02 · 15 answers · asked by Allen 2

does science leave any room for religion now that its discovered theories of relativity, superstring theory, BIG BANG THEORY!, wormholes, blackholes, stars, etc..... why have religioin anymore? everything has chance not luck. everything has reason not a supernatural "thing" controling it. Matter is not created by "god" it is eternal. What is the use of religion when it is so unaccurate to the creation of the universe???

2007-09-14 16:37:31 · 4 answers · asked by Allen 2

Picture the corner of a room. Imagine the corner of a room. Let's say that the left wall leading into the corner is labeled 1, the corner itself is labeled 2, and the right wall leading from the corner 3 (I hate that I can't draw here!). O.K., a cat runs across the floor from 1 to 2 to 3 without increasing or decreasing his speed. He only changes his direction of motion at 2 (the corner). Can we say for sure that a force was exerted on the cat at 2?

a) Yes, there had to be a force on the cat at 2.
b) Not necessarily, since no change in the cat's speed occurred.

2007-09-14 16:21:21 · 2 answers · asked by ? 6

a) A particle executes simple harmonic motion with an amplitude of 3 cm. At what position des its speed equal one half of its maximum speed?

b) A 65kg bungee jumper steps off a bridge with a light bungee cord tied to her and to the bridge. The unstretched length of the cord is 11m. The jumper reaches the bottom of her motion 36m below the bridge before bouncing back. Her motion can be separated into an 11m free fall and a 25m section of simple harmonic osciilation.
- For what time interval is she in free fall?
- Use the principle of conservation of energy to find the spring constant of the bungee cord.

2007-09-14 15:55:44 · 1 answers · asked by Jay Z 1

An airplane is heading due south at a speed of 560 km/h. If a wind begins blowing from the southwest at a speed of 100 km/h (average), calculate the following.

(a) the velocity (magnitude and direction) of the plane relative to the ground
=........km/h .........° (east of south)

(b) how far from its intended position will it be after 10 min if the pilot takes no corrective action. [Hint: First draw a diagram.]
=.....km

2007-09-14 15:50:56 · 1 answers · asked by Nikita 1

A speed ramp at an airport is basically a large conveyor belt on which you can stand and be moved along. The belt of one speed ramp moves at a constant speed such that the person who stands still on it leaves the ramp 64 seconds after getting on. Clifford is on a real hurry, however, and skips the speed ramp. Starting from rest with an acceleration of 0.37 m/s^2, he covers the same distance as the ramp does, but does in one-fourth of the time. What is the speed at which the belt of the ramp is moving?

You may need the following equations:
v=v0+at
x=x0+v0t+1/2a(t^2)
v^2=v0^2+2ax

2007-09-14 15:12:45 · 1 answers · asked by Anonymous

a person is falling from the plane
with drag = -1.5v
how long till he falls 10000 ft
please show all work

2007-09-14 15:05:48 · 4 answers · asked by Anonymous

A speed ramp at an airport is basically a large conveyor belt on which you can stand and be moved along. The belt of one speed ramp moves at a constant speed such that the person who stands still on it leaves the ramp 64 seconds after getting on. Clifford is on a real hurry, however, and skips the speed ramp. Starting from rest with an acceleration of 0.37 m/s^2, he covers the same distance as the ramp does, but does in one-fourth of the time. What is the speed at which the belt of the ramp is moving?

You may need the following equations:
v=v0+at
x=x0+v0t+1/2a(t^2)
v^2=v0^2+2ax

2007-09-14 14:37:40 · 1 answers · asked by Anonymous

A quarterback claims that he can throw the football a horizontal distance of 176 m. Furthermore, he claims that he can do this by launching the ball at the relatively low angle of 25.4 ° above the horizontal. To evaluate this claim, determine the speed with which this quarterback must throw the ball. Assume that the ball is launched and caught at the same vertical level and that air resistance can be ignored. For comparison a baseball pitcher who can accurately throw a fastball at 45 m/s (100 mph) would be considered exceptional.

2007-09-14 14:36:04 · 4 answers · asked by lonelygirlinhell 1

A train moves at a constant speed of 60 km/h toward a station 30 km away. At that moment Fanny Fastbird leaves her perch on the locomotive and flies toward the station at a constant speed of 100 km/h relative to the ground. When the bird reaches the station, she immediately turns around and flies back to the train at the same speed. When reaching the train she again immediately turns around and flies back to the station, repeating the process until the train passes the station. What total distance is traveled by the bird?


Thank you so much for your help! I am curious as to how I would solve this problem, and the more steps shown, the better. Thank you!

2007-09-14 14:24:00 · 3 answers · asked by Anonymous

2007-09-14 14:22:36 · 5 answers · asked by DROCK 1

hello everybody

in class i did an experiment and i lunched a metal cart down a ramp and recorded the data from the ticker timer and than i plotted a position- time graph.

http://img466.imageshack.us/my.php?image=positionvstimemt0.jpg

one of the questions asks what type of motion was the cart undergoing? and how can you tell by the shape of the graph?

what would you guys/girls the answer is for the above questions?(i included a photo of the graph above)

thanks alot!:)

2007-09-14 14:13:40 · 2 answers · asked by Anonymous

Is there a way to get water to 100 degrees c and not boil , i think i know , as you can also get water to boil at 40 degrees c , under certain circumstances.

2007-09-14 12:59:30 · 23 answers · asked by 株式会THE CITADEL 株式会 4

pls choose bet. mass and weight and why?

2007-09-14 12:19:55 · 2 answers · asked by daisy 2

A car moving westward along a straight level road increases its velocity uniformly from +19 m/s to +37 m/s in 11.2 seconds.

What is the car's acceleration in m/s^2?
How far did it move while accelerating? Answer in units of m.
What was its average velocity in m/s?

Please explain the steps in solving this problem.

2007-09-14 12:18:52 · 2 answers · asked by Anonymous

Calculate (a) the time it takes for the ball to reach its highest point; (b) the highest distance reached; (c) the distance and velocity after t = 2 s. and (d) the time it takes to reach the ground.

2007-09-14 12:12:32 · 3 answers · asked by Pascal 4

If it starts from rest, moves with constant acceleration, and becomes airborne in time 7.10 s, what is its speed when it takes off?

2007-09-14 12:07:10 · 5 answers · asked by bg 1

A rocket driven sled runnung on a straight level track has been used to study physiological effects on large accelerations on astronauts. One such sled can attain a speed of 361 m/s in 1.7 s starting from rest. What is the acceleration of the sled, assuming it is constant? Answer in units of meters per seconds squared(m/s^2)

2007-09-14 11:05:54 · 4 answers · asked by Anonymous

Why is it so difficult to stop or turn a supertanker?

2007-09-14 10:44:16 · 4 answers · asked by kntagler 1

The raduis of rotor R = 9m
Mass of helicoper is M = 10 tonnes + 5 x (m = 120 kg blages)
Velocity of the tips of the blades is v = 300 m/s
http://www.sa-transport.co.za/aircraft/military/mi-24_hind_d_ajk.JPG

What is the angle of the cone formed by the rotor?

2007-09-14 10:01:05 · 4 answers · asked by Alexander 6

the first and second pitches, and the force with which the baseball is hit is the same on both pitches that i can calculate that if the first pitch was hit with an angle of 45 degrees to the ground, that it will go farther than a second hit at an angle of 75 degrees. my question is what happens if the everything is the same for a third scenario, but the speed of the pitch varies. will the ball go farther if the pitch is thrown faster? and does it go farther based on the same proportionality rules as the first two scenarios, or does speed count for more distance, than say angle, and force?

2007-09-14 09:33:21 · 1 answers · asked by Backtash123 1