Physics - April 2007

My Guide wants me to get answer in terms of
Ampere per Metre. The units I m getting are :

Volt * Second/metre^2.

Kindly give suitable reason.

2007-04-10 18:54:20 · 2 answers · asked by Gaurav 1

Ok, I get it. I've seen the twin paradox, I've seen the ladder paradox, I know how to calculate time dilation and contraction and composition of velocities, etc. etc. But a few hours ago the question again popped into my mind: why does special relativity happen?

I'm sure it has something to do with the speed of light being constant, but my head's been spinning for hours and I can't figure it out. Can someone sum it up for me or at least put me on the right track?

2007-04-10 18:31:18 · 5 answers · asked by croato87 5

A block of 1 kg mass is pulled from rest in the horizontal x-direction with a displacement dependent force of F=4x+2. The rope makes a 30 degree angle with the floor. What is the change in kinetic energy?

2007-04-10 16:54:37 · 2 answers · asked by AdrianG430 1

I'm just looking for some brainstorm seeds - it's a topic I'm considering for a piece of work, but I'm not sure where to go with it. What might you use as a non-rigid support? How does it change the equations (assuming that the small-angle approximation still works on the pendulum)? Stuff like that.

2007-04-10 16:46:27 · 3 answers · asked by rissaofthesaiyajin 3

Show that the kinetic energy of an object rotating about a fixed axis with angular momentum L = Iw can be written as K = L^2 / 2I

L = angular momentum
I = moment of inertia
w = (omega) = angular velocity

I'm not sure if I should approach this problem using dimensional analysis or with some other means

2007-04-10 16:41:54 · 1 answers · asked by mikeo853 1

The drawing shows four point charges. The value of q is 2.2 µC, and the distance d is 0.94 m. Find the total potential at the location P. Assume that the potential of a point charge is zero at infinity.

IMAGE:
http://www.webassign.net/cj/p19-16.gif...

Now I found that

"The key to this problem is the principle of superposition, which states that the interaction of two charges is unaffected by the presence of other charges. This applies to forces, fields, and potentials. So to calculate the total ppotential at P, first calculate the potential at point P due to each of the four charges, ignoring the other charges. Then add them all up. "
for this answer, but it did not help me much, still did not understand, nor got the answer right.

http://answers.yahoo.com/question/index;...

Help? Thanks!

2007-04-10 16:20:42 · 1 answers · asked by Andy 1

2007-04-10 16:15:19 · 4 answers · asked by ashraf_saiyed 1

A crane uses a block and tackle to lift a 2200 N flahstone to a height of 25 m.
b. In the process, the cranes hydraulic motor does 110 kJ of work
on the cable in the block and tackle. What is the effiency. (Just checking i got 2%)

c. What is the potential energy of the flagstone when it is 25 m above the ground? (On this one I could not find mass)

2007-04-10 16:14:25 · 2 answers · asked by Anonymous

2007-04-10 16:11:08 · 3 answers · asked by ashraf_saiyed 1

2007-04-10 15:57:45 · 7 answers · asked by Anonymous

2007-04-10 15:52:16 · 5 answers · asked by Anonymous

Ok, this is a tangential and centripetal acceleration conceptual question:

"The gas pedal and the brakes of a car accelerate and decelerate the car. Could a steering wheel fall into either of these categories? Explain."

10 points for the first good answer.

2007-04-10 15:17:19 · 16 answers · asked by Anonymous

_____ J

* Circuits

2007-04-10 15:16:14 · 5 answers · asked by Khoi 1

Figure P17
http://www.webassign.net/hecht/18-P15.gif

_____ A (before)
_____ A (after)

* Circuits

2007-04-10 15:13:43 · 1 answers · asked by Khoi 1

2007-04-10 15:12:36 · 1 answers · asked by wtf is this hellhole 2

A crate of mass 13.0 kg is pulled up a rough incline with an initial speed of 1.50 m/s. The pulling force is 100 N parallel to the incline, which makes an angle of 20.0° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 5.95 m.
(a) How much work is done by gravity?
-259.53
(b) How much mechanical energy is lost due to friction?
285.22 J
(c) How much work is done by the 100 N force?
595 J
(d) What is the change in kinetic energy of the crate?
50.26 J
(e) What is the speed of the crate after being pulled 5.95 m?


I got the right answer for the others, but I cant figure out how to do E, any help?

2007-04-10 15:00:32 · 2 answers · asked by Erin C 1

The evaporation of perspiration is the primary mechanism for cooling the human body. Determine the amount of water you will lose when you bake in the sun on the beach for an hour. Use a value of 900 W/m2 for the intensity of sunlight, assume that the area of your body exposed to the sun is 0.61 m2 and that your skin temperature is 37°C, and note that the energy required to evaporate a liquid at a particular temperature is approximately equal to the sum of the energy required to raise its temperature to the boiling point and the latent heat of vaporization (determined at boiling point).

the formula i was trying to use is stephan's law but that didnt seem to work.

Any help with this problem would really help me out, thanks!

2007-04-10 14:53:54 · 2 answers · asked by Kacey L 1

it then slides 25 m before coming to rest. the coeficient of kinetic friction between the object and the floor is

2007-04-10 14:46:01 · 1 answers · asked by l_walker2005 1

2007-04-10 14:43:42 · 6 answers · asked by Anonymous

In a race over a distance s, runner A starts from rest and accelerates at a_1 for the first distance x and then runs at constant speed. Runner B starts from rest and accelerates at a_2 for the first distance x and then runs at constant speed. Runner A begins running as soon as the race begins but B first takes a nap to rest up.

What is the longest nap that B can take and still not lose the race?

2007-04-10 14:20:21 · 1 answers · asked by Anonymous

Speed and net work of bead down a frictionless track?

A bead of mass m = 5.10 kg is released from point A and slides on the frictionless track shown in Figure P5.30. The height of A is ha = 5.90 m.

Figure P5.30: http://i165.photobucket.com/albums/u78/RLB31384/p5-30alt.gif
(a) Determine the bead's speed at points B and C. point B m/s
point C m/s
(b) Determine the net work done by the force of gravity in moving the bead from A to C.

2007-04-10 14:14:43 · 1 answers · asked by Erin C 1

Also, why is a "high quality" meter rated with a higher value of ohms/volt? Any help is much appreciated!

2007-04-10 14:10:42 · 3 answers · asked by KrazySweetie 4

Speed and net work of bead down a frictionless track?

A bead of mass m = 5.10 kg is released from point A and slides on the frictionless track shown in Figure P5.30. The height of A is ha = 5.90 m.

Figure P5.30: http://i165.photobucket.com/albums/u78/RLB31384/p5-30alt.gif
(a) Determine the bead's speed at points B and C. point B m/s
point C m/s
(b) Determine the net work done by the force of gravity in moving the bead from A to C.

2007-04-10 14:01:30 · 1 answers · asked by Erin C 1

I don't understand what this is asking. Here is all the information that is given.

Two people are carrying a uniform wooden board that is 3.00 m long and weighs 160 N.

The answer should be ____ m from the point where the 60 N force is applied.

2007-04-10 13:56:47 · 1 answers · asked by Devin B 1

A crate of mass 13.0 kg is pulled up a rough incline with an initial speed of 1.50 m/s. The pulling force is 100 N parallel to the incline, which makes an angle of 20.0° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 5.95 m. The change in kinetic energy of the crate is 50.26 J.

What is the speed of the crate after being pulled 5.95 m?

2007-04-10 13:54:25 · 1 answers · asked by Erin C 1

Speed of crate after being pulled 5.95m?

A crate of mass 13.0 kg is pulled up a rough incline with an initial speed of 1.50 m/s. The pulling force is 100 N parallel to the incline, which makes an angle of 20.0° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 5.95 m. The change in kinetic energy of the crate is 50.26 J.

What is the speed of the crate after being pulled 5.95 m?

2007-04-10 13:09:02 · 1 answers · asked by ? 1

I have a physics exam tomorrow and I have to explain this as an essay question. I need to know a lot of details. Thanks!

2007-04-10 13:03:37 · 8 answers · asked by Kaitlyn 2

Please help me: a 1500 kg train container is traveling horizontally at 5.0m/s. It passes a wheat chute which vertically drops a load of grain into the container in 5s the container full of grain slows to 1.2 m/s how much grain was deposited and what is the horizontal impulse of the container and grain together?

2007-04-10 12:57:38 · 1 answers · asked by skybluu 2

If 50.0 g of ice at 0.0 degrees C is addd to 150.0 g of water at 80.0 degrees C, what will the temperature of the mixture be when it reaches thermal equilibrium?

how do you solve that after you change the g into kg and the celcius into kelvin?

2007-04-10 12:53:47 · 1 answers · asked by Dan 2

A claw hammer is used to pull a nail out of a board. The nail is at an angle of 60 degrees to the board, and a force F1 of magnitude 500 N applied to the nail is required to pull it from the board. The hammer head contacts the board at point A, which is 0.080 m from where the nail enters the board. A horizontal force F2 is applied to the hammer handle at a distance of 0.300 m above the board.

http://session.masteringphysics.com/problemAsset/1008098/4/yf_Figure_11_30.jpg

2007-04-10 12:45:51 · 1 answers · asked by Devin B 1