Physics - December 2006

hi..im looking for physics chat rooms on the net
does any body know the website for one? or how i can find one..
thanx

2006-12-13 18:43:25 · 2 answers · asked by bobby19_9 1

Joe and Sally are ice-skating northwards side by side. joe weighs 100kg and sally weighs 60kg. sally is carrying a package that weighs 10kg.

a) what is joes initial momentum?
b) what is sally's initial momentum?
c) what is the initial momentum of the box?

Please show how you got the answer and best answer gets 10 points!!

2006-12-13 18:27:11 · 2 answers · asked by bobby19_9 1

2006-12-13 18:07:02 · 8 answers · asked by 408 1

2006-12-13 17:50:14 · 3 answers · asked by elwinwebb 1

An object of mass m is hanging by a string from the roof of a car. We want to compare the tension in the string to the weight of the object under various conditions. Which statements are true?

1. If the car is moving forward, and speeding up, the tension in the string is less than the object's weight.
2. if the car has left the ground going over a bump, the tension in the string is greater than the object's weight.
3. If the car is turning to the right, the tension in the string is less than the object's weight.

2006-12-13 17:38:22 · 2 answers · asked by WMC 1

A 5.00 g bullet is fired with a velocity of 1.00 x 10^2 m/s toward a stationary solid block resting on a frictionless surface.

a) What is the change in momentum of the bullet if it embeds in the block?

b)What is the change in momentum of the bullet if it ricochets in the opposite direction with a speed of 99 m/s - almost the same speed as it had originally?

c) In which case does the block acheive the greatest velocity?

2006-12-13 16:50:16 · 0 answers · asked by Churro 2

In the laboratory, you are asked to determine the mass of a meter stick without using a scale of any kind. In addition to the meter stick, you may use any or all of the following equipment:

1.) a set of known masses, 2.) four weight hangers, 3.) tape, 4.) a fulcrum upon which the meter stick can be mounted and pivoted, 5.) string, 6.) stopwatch

Briefly list the steps in your procedure that will lead you to the mass of the meter stick. Include definitions of any parameters that you will measure.

Indicate which pieces of equipment will be used.

Show the calculations you would perform to find the mass of the meter stick.

2006-12-13 16:20:09 · 2 answers · asked by Robin 3

As the captain of the scientific team sent to Planet Physics, one of your tasks is to measure gravity. You have a long, thin wire labeled 1.15 g/m and a 1.22 kg weight. You have your accurate space cadet chronometer but, unfortunately, you seem to have forgotten a meter stick. Undeterred, you first find the midpoint of the wire by folding it in half. You then attach one end of the wire to the wall of your laboratory, stretch it horizontally to pass over a pulley at the midpoint of the wire, then tie the 1.22 kg weight to the end hanging over the pulley. By vibrating the wire, and measuring time with your chronometer, you find that the wire's second harmonic frequency is 200 Hz . Next, with the 1.22 kg weight still tied to one end of the wire, you attach the other end to the ceiling to make a pendulum. You find that the pendulum requires 313 s to complete 200 oscillations. Pulling out your trusty calculator, you get to work.

What value of gravity will you report back to headquarter

2006-12-13 16:05:04 · 4 answers · asked by MattS 1

Gravity on Another Planet
After landing on an unfamiliar planet, a space explorer constructs a simple pendulum of length 53.0 cm . The explorer finds that the pendulum completes 105 full swing cycles in a time of 144 s.
What is the value of the acceleration of gravity on this planet?
Express your answer in meters per second per second. m/s^2

2006-12-13 15:58:07 · 4 answers · asked by MattS 1

2006-12-13 15:51:00 · 9 answers · asked by Anonymous

2006-12-13 15:38:08 · 3 answers · asked by arn_14 2

A little spider monkey (let’s call her Flo) has stolen a bunch of bananas from her older brother Charley and is now running away from him with the bananas in hand. She sees salvation in a long vine and grabs the bottom, hoping to swing away.


If Flo, who has a mass of 5.3 kg, and the bananas, with a mass of .5 kg, reaches a height of 1.2 m before slowing to a stop and swinging back down, how fast was she running when she grabbed the vine?


As she swings back down, Charley (whose mass is 5.9 kg) is standing just at the bottom of the swing. He grabs her and they swing up together. What height will the two monkeys and the coveted bananas reach?

i already answered the 1st ? and i got 4.85m/sec
i need help with the 2nd ? plz

2006-12-13 15:36:48 · 1 answers · asked by fnnybunny45 1

Problem 11.74
As a hobby, you like to participate in reenactments of Civil War battles. Civil War cannons were "muzzle loaded," meaning that the gunpowder and the cannonball were inserted into the output end of the muzzle, then tamped into place with a long plunger. To recreate the authenticity of muzzle-loaded cannons, but without the danger of real cannons, Civil War buffs have invented a spring-powered cannon that fires a 1.0 kg plastic ball. A spring, with 3000 N/m spring constant , is mounted at the back of the barrel. You place a ball in the barrel, then use a long plunger to press the ball against the spring and lock the spring into place, ready for firing. In order for the latch to catch, the ball has to be moving at a speed of 2.0m/s at least when the spring has been compressed 30 cm. The coefficient of friction of the ball in the barrel is 0.30. The plunger doesn't touch the sides of the barrel.
If you push the plunger with a constant force, what is the minimum force that you must use to compress and latch the spring? You can assume that no effort was required to push the ball down the barrel to where it first contacts the spring.
What is the cannon's muzzle velocity if the ball travels a total distance of 1.5 m to the end of the barrel?

2006-12-13 15:33:45 · 1 answers · asked by Anonymous

Just as Ptolemy's epicycles attempted to force the observed nature of the world to agree with the then held geocentric philosophy, could Einstein be wrong about the speed of light?

2006-12-13 15:32:45 · 7 answers · asked by Anonymous

With the latest space mission to continue construction of the ISS, it occurred to me, are we resilient enough to recover from zero gravity from extended periods of time in space, even as little as a week? It seems to me that after a week in space simple movements on earth must feel like the equivalent of the G-forces a fighter pilot must feel when flying an F-16 or something.

2006-12-13 15:28:50 · 5 answers · asked by Anonymous

when I stand next to it, but when I walk away it's terrible.

2006-12-13 15:26:18 · 6 answers · asked by massadaman 4

okay so a hw question says...'' this metal is very reactive, has properties similar to those of magnesium, and in the same period as bromine. does anyone know which element this is???

also..do you know what this one is...''this nonmetal is in the same group as lead" btw..i cant find lead on the table..

please helpp!!

thankk you sooo much!!

2006-12-13 15:21:34 · 3 answers · asked by thetachibabe 3

reed used caplet (antacid i suspect) and some liquid to turn a film caniste into a rocket .
My question is dose any one know what the liquid was,and know for shure what the caplet was if not antacid

2006-12-13 15:19:09 · 1 answers · asked by Anonymous

Problem 7.64
You are flying to New York. You've been reading the in-flight magazine, which has an article about the physics of flying. You learned that the airflow over the wings creates a lift force that is always perpendicular to the wings. In level flight, the upward lift force exactly balances the downward weight force. The pilot comes on to say that, because of heavy traffic, the plane is going to circle the airport for a while. She says that you'll maintain a speed of 400 mph at an altitude of 20,000 ft. You start to wonder what the diameter of the plane's circle around the airport is. You notice that the pilot has banked the plane so that the wings are 10 degrees from horizontal. The safety card in the seatback pocket informs you that the plane's wing span is 250 ft.

What is the diameter of the airplane's path around the airport?

2006-12-13 15:08:34 · 3 answers · asked by physicsmed22 1

A 60Kg object is moving at 20m/s when a force brings the object to rest in 0.050 seconds. If the same object moving at the same initial speed was brought to rest in 0.50 seconds, then the required force would be__, the resulting impulse would be__ and the resulting momentum change would be__. List all three answers in order



a. the same as the original value
b. two times the original value
c. ten times the original value
d. one-half of the original value
e. one-tenth or the original value
f. None of these choices feel this blank

2006-12-13 15:00:02 · 2 answers · asked by "G" 1

A spring with spring constant of 27 N/m is
stretched 0.12m from its equilibrium position.
How much work must be done to stretch it
an additional 0.059 m? Answer in units of J.

2006-12-13 14:53:45 · 2 answers · asked by Anonymous

A skyrosket explodes 90m above the ground. Three observers are spaced 82. apart, with observer A directly under the point of the explosion. Find the ratio of the sound intensity heard by observer A to that heard by observer B. Find ratio of intensity heard by observer A to that heard by observer C.

2006-12-13 14:49:10 · 2 answers · asked by smb473 1

2006-12-13 14:47:22 · 6 answers · asked by manna eater 3

At what minimum speed must a roller coaster be traveling when upside down at the top of a circle so that the passengers will not fall out? Assume a radius of curvature of 9.4 m.

2006-12-13 14:38:14 · 1 answers · asked by jang k 1

I hear it is a by product of U-238, so is it possible for a terrorist to make a nuke from it?

2006-12-13 14:33:34 · 5 answers · asked by Anonymous

A car moving at 19 m/s drives over the top of a hill. The top of the hill forms an arc of a vertical circle 140 meters in diameter.
•What is the centripetal force holding the car in the circle?
•What therefore is the normal force between the car's tires and the road?

2006-12-13 14:20:07 · 2 answers · asked by tanie 1

A boulder that weighs 200 N is posed on the edge of a 100-meter cliff. What is its gravitational potential energy? Draw a diagram showing how its potential energy and kinetic energy change as it falls to 50 m, 20 m, and 10 m. I have this as a question in 9th grade Physics, don't get how to draw the diagram, get everything else.

2006-12-13 14:16:25 · 2 answers · asked by Zach S 5

chemical reaction occurs when 2 substances, because of their molecular structure, produce a chemical change when they come into contact.

2006-12-13 14:09:44 · 5 answers · asked by Anonymous

My professor once told me that the lower the temperature of the water being heated, the faster it takes for it to boil unlike the ones with the higher temperature, i just want to know ALL the reasons behind it.. :D

2006-12-13 14:02:15 · 13 answers · asked by Anonymous

I personally believe that our 3D bodies are not designed to experience a 4th dimension. However, I also believe the 4th dimension is of the spiritual realm.

2006-12-13 13:41:26 · 6 answers · asked by Anonymous