Physics - July 2007

If you were in the water, how far away would you have to be to avoid being electrocuted?

2007-07-23 04:38:01 · 3 answers · asked by Anonymous

A rod with mass M = 1.4 kg and length L = 1.2 m is mounted on a central pivot . A metal ball of mass m = 0.7 kg is attached to one end of the rod. You may treat the metal ball as a point mass. The system is oriented in the vertical plane and gravity is acting. The rod initially makes an angle θ = 27 with respect to the horizontal. The rod is released from rest. What is the angular acceleration of the rod immediately after it is released?

2007-07-23 04:19:30 · 3 answers · asked by Anonymous

1. Suppose a classmate of yours has missed lecture for the last week. Write a full solution of the following problem so that your classmate can use it to help catch up with the material. you need to explain in detail each step of the precess you use to get to an answer.

a sled weighing 100.0N is pulled horizontally across snow so that the coefficient of kinetic friction between sled and snow is 0.2. A penquin weighing 70.0N rides on the sled, as in the figure.
(a) to start with, the penquin digs in his claws so he is firmly attached to the sled. What value of F do you need for the sled and penguin to move at constant speed?
(b) after a while, our penguin gets tired of holding on with his claws. Now the coefficient of static friction between penguin and sled is 0.7, find the maximum horizontal force that can be exerted on the sled before the penguin begins to slide off.

2007-07-23 04:19:10 · 2 answers · asked by sdajc0603 2

A passennger on a bus moving with uniform velocity lurches forward when the bus stops suddenly. Explain.

2007-07-23 04:07:20 · 3 answers · asked by emmasahottie 3

i need this urgently for my science project . please help out !

okay basically , we have to describe a phenomena. in this case, its when i lean my left foot and left shoulder against a wall , i am unable to lift up my right foot . try it . you really cant .
i need the concept behind it , but i cant find it anywhere . really need help . if you know anything or hv any websites to recommend, please tell me ! THANKS .
btw, some examples of the concept : centre of gravity . when i lean against the wall my centre of gravity is not balanced . thus , blablabla . something lik that .

2007-07-23 04:02:08 · 6 answers · asked by Anonymous

A car accelerated from 6.00 m/s to 20.0 m/s, over a distance of 50 m. What is the rate of acceleration??

2007-07-23 03:38:20 · 3 answers · asked by Leah B 1

If you use a current limiting resistor, it will get extremely hot, and will waste energy. By using a capacitor, no heat is dissipated in the capacitor. My question is, how much electricity will I use? To get 20mA through the LED, surely I am going to use 20mA at 110V. So where does the energy go?
And can someone offer a calculation for the capacitance to run a 2v 20mA LED. Thanks.

2007-07-23 03:37:32 · 2 answers · asked by Experimentor 2

2007-07-23 03:11:41 · 12 answers · asked by Anonymous

2007-07-23 03:05:13 · 9 answers · asked by kmof6322 1

Explain, using Huygen’s principle, how refraction occurs due to a change of wave speed as the wave moves from one medium to another.

2007-07-23 03:04:44 · 3 answers · asked by acu04385 2

The resistances of the primary and secondary coils of a transformer are 45 and 13 , respectively. Both coils are made from lengths of the same copper wire. The circular turns of each coil have the same diameter. Find the turns ratio Ns/Np.

2007-07-23 03:01:07 · 2 answers · asked by cwhughes13 2

A 200-g block is pressed against a spring of force constant 1.40 kN/m until the
block compresses the spring 10.0 cm. The spring rests at the bottom of a ramp inclined at
60.0° to the horizontal. Using energy considerations, determine how far up the incline the
block moves before it stops (a) if there is no friction between the block and the ramp and
(b) if the coefficient of kinetic friction is 0.400.

2007-07-23 01:49:06 · 2 answers · asked by radwan M 1

2007-07-23 00:52:25 · 5 answers · asked by shakti 1

Physics question.?
"A terrorist, 800 metes from a take off point of a plane is about to hit the plane using a rocket launcher with a velocity of 280 meters per second inclined 30 degrees within the ground. If the plane has the take-off velocity of 100 meters per second at 15 degrees, how long will it take after the take-off before the rocket is fired in order to hit the target?show solution.

2007-07-23 00:23:04 · 1 answers · asked by Monica D 2

And if it does, then how is it measured?

2007-07-22 21:05:29 · 6 answers · asked by Anonymous

Focus lens system which has no mechanical moving parts

its was recently developed by philps

dear friends do u have any information regrading this topic pl z reply

2007-07-22 19:54:38 · 1 answers · asked by nithin n 1

2007-07-22 19:18:45 · 3 answers · asked by Anonymous

Can you get neodymium magnets in sheet form and if so are sheet magnets weaker or stronger than other ones(disc, cube etc)?

2007-07-22 19:02:43 · 2 answers · asked by ntm495 4

2007-07-22 18:56:14 · 9 answers · asked by Ashley H 1

A) 74km/h
B)69 km/h
C)70km/h
D) cannot tell
C)140km/h

2007-07-22 18:14:49 · 3 answers · asked by Anonymous

If time/space is measured threw entropy (from ordered state to chaos) than what if there was no one here to make the initial measure. Would the laws of entropy still apply?

2007-07-22 18:08:31 · 2 answers · asked by Andrew 3

At what point will gravity equalize and attract the opposite direction? Think about it you that claim to be scientific minded. james h. Why else would you weigh the same on the poles as you do on the equator? Thinner earth on the poles as a result of centrifugal force of spinning.

2007-07-22 18:02:55 · 1 answers · asked by james h 2

A bubble with a volume of 1.0 cm^3 forms at the bottom of a lake that is 20.0 m deep. The temperature at the bottom of the lake is 10.0 degrees C. The bubble rises to the surface where the temperature is 25.0 degrees C. Assume that the bubble is small enough that its temperature always matches that of its surroundings.

2007-07-22 17:56:22 · 3 answers · asked by Anonymous

2007-07-22 17:17:47 · 3 answers · asked by Anonymous

2007-07-22 16:35:40 · 11 answers · asked by superlanggam 1

Why are there never any good, mind-boggling questions here in Physics? All I usually see are boring homework problems. Why is that?

2007-07-22 16:19:12 · 8 answers · asked by Anonymous

A wildfire is approaching a window. A sheet of insulated material(non flammable) is being adhered to the window using suction cups. The Fire is 1000 F max..the windows maximum temperature heated temp is 300F but only avg 100F for first 20 minutes..Will the suction cups pop off in first 20 minutes...? At all? Would size of cup make a difference..

2007-07-22 16:16:58 · 2 answers · asked by d k 1

A horizontal wire carries a current straight toward you. From your point of view, the magnetic field caused by this current

a) points directly away from you
b)points to the left
c)circles the wire in a clockwise direction
d)circles the wire in a counter-clockwise direction

2007-07-22 15:50:44 · 2 answers · asked by Kel 1

For electric forces, similar charges repel and opposites attract. For magnetic forces, similar poles repel and opposites attract.

How come magnetic forces acting between wires, appear to violate this symmetry? How come it is not a violation (only appears to be a violation)?

2007-07-22 14:30:34 · 4 answers · asked by Anonymous

2007-07-22 14:24:19 · 10 answers · asked by Anonymous