Physics - December 2007

Yes,still homework..... so help people?!

2007-12-08 13:58:49 · 7 answers · asked by Seraphim S 1

You want to take a bath with the water temperature at 35.0°C. The water temperature is 38.0°C from the hot water tap and 11.0°C from the cold water tap. You fill the tub with a total of 197 kg of water. How many kilograms of water from the hot water tap do you use?

2007-12-08 13:24:35 · 3 answers · asked by Phaedrius 2

Does
E=mc^2
mean that energy has mass?

2007-12-08 13:06:28 · 8 answers · asked by ilovethechub 2

Physicist, quantum theorist, cosmologist.
Can someone explain to me what these are?
What has he done?

2007-12-08 12:35:59 · 7 answers · asked by Anonymous

A skier starts from rest at the top of a hill that is inclined at 11.1 degrees with the horizontal. The hillside is 174.8 m long, and the coefficient of friction between the snow and the skis is 0.067. At the bottom of the hill, the snow is level and the coefficient of friction is unchanged.
The acceleration of gravity is 9.81 m/s2
How far does the skier move along the horizontal portion of the snow before coming to rest? Answer in units of m.

Thanks for any help! :)

2007-12-08 12:31:16 · 2 answers · asked by Catalina 2

Two masses are 2.9 kg each. The first mass is moving with a velocity v1 immediately before colliding with the second mass, which is suspended by a string of length 1m. The 2 masses are stuck together as a result of the collision. The compound system then swings to the right and rises to the horizontal level. The acceleration of gravity is 9.8m/s/s.

I drew a diagram for this problem, which can be found at http://img363.imageshack.us/img363/6962/physicssv4.jpg

Find the kinetic energy of the compound system immediately after the collision. Answer in units of J.

Any help is greatly appreciated! Thanks!

2007-12-08 12:18:52 · 2 answers · asked by thiscouldbetricky 1

Okay, this is strictly hypothetical. Just for fun, that is. The only criterion for getting Best Answer is to make me say "Hmmm...Interesting." Got it?

It's the distant future, and scientists have just perfected a matter transporter that allows humans to travel great distances at essentially the speed of light. It works by rapidly encoding every bit of information about the atoms that make up your body (down to the tiniest quantum detail), then disintegrating you, beaming the information to your destination, and reassembling you atom-for-atom. I know, I know...it's pure fantasy. But here's the question: Is it still YOU? Does it have your memories, your hopes, your dreams? Or is it just a copy of you, albeit a remarkably precise one? What do you think, folks?

If it's NOT you, is that person still accountable for your debts? If a murderer travels through the matter transporter, can he or she still be tried for murder, even though it's not the "same person"?

2007-12-08 12:03:20 · 3 answers · asked by Lucas C 7

what is 5(mu)T? what does that number equal to??? or (mu)T?

2007-12-08 11:27:20 · 2 answers · asked by biscuits 2

anyone know? i haven't found the legality of trebuchets in any state, county, or city, on any websites.

my neighbors and the people at home depot all thought they were illegal, but it's my physics project that i was assigned to do lol. and now i'm wondering if i'm gonna get in trouble if i test launch it anywhere.....

2007-12-08 10:56:07 · 2 answers · asked by Anonymous

Example, for natural numbers, 1,2,3,4,5...............infinity. and for real numbers .

2007-12-08 10:47:36 · 7 answers · asked by omid 1

Does it have to do with it being a longitudinal wave? Or does it need an entirely different index of refraction?
I'm really confused because when I used an equation from a textbook and compared sound in air to water, the speed of sound in air was faster than it in water.

2007-12-08 10:45:42 · 7 answers · asked by Eileen 1

Okay, you hit the little white pool ball. The little white ball hits another ball (lets say the 8 ball).

I think the 8 ball CAN NOT travel at a faster speed than the white ball you initially hit (given a flat table, no wind, etc). My friend is arguing that it can. Can someone give me any pertinent physics or equations to back me up on this?

2007-12-08 10:06:23 · 3 answers · asked by Roberto 3

can someone help plz i will choose a best answer

It has been argued that power plants should make use of off-peak hours (such as late at night) to generate mechanical energy and store it until it is needed during peak load times, such as the middle of the day. One suggestion has been to store the energy in large flywheels spinning on nearly frictionless ball-bearings. Consider a flywheel made of iron, with a density of 7800 kg/m^3, in the shape of a uniform disk with a thickness of 12.1 cm.

1) What would the diameter of such a disk need to be if it is to store an amount of kinetic energy of 15.0 MJ when spinning at an angular velocity of 90.0 rpm about an axis perpendicular to the disk .

2) What would be the centripetal acceleration of a point on its rim when spinning at this rate?

thank you so much in advance and i will choose a best answer

2007-12-08 09:28:21 · 2 answers · asked by Need help plz!!! 1

Please help me with this one, we had a test and no one (!) could figure that problem out. (9th grade physics)
btw I don't live in America so I had to translate it..sorry

object A is released from a top of a building and falls. At the same moment object B is fired from the ground upwards, with a starting velocity that allowes it's apex to be the building height.
When the two bodies pass by, B's velocity is 12.25 m/s .

a. What is A's velocity at the moment they pass by?

b. What is B's starting velocity?

c. How tall is the building?

d. When the objects pass by, what is their height?

And again, sorry if I translated it wrong or something..

2007-12-08 08:00:25 · 3 answers · asked by Anonymous

2007-12-08 07:10:03 · 11 answers · asked by xbabysashx111 1

And if there a set time how can that time be calculated?

2007-12-08 06:46:42 · 3 answers · asked by Anonymous

Science question for a final study guide. A 1kg car will accelerate (faster, slower, the same) as a 2 kg car when rolling down a frictionless ramp.
I thought it was the same but am not sure.

2007-12-08 06:41:10 · 5 answers · asked by onlyhope117 1

Hi,

I am working with a group of people on a physics project based on projectile motion. Our task is to build a ping pong launcher that will launch ping pongs into a bin 3.5 to 4.5 meters away from a line. The launcher must be behind this line. Furthermore, the ball can only be launched at a maximum of 30 cm above ground level. Do you have any suggestions that can help us construct our project?

2007-12-08 06:32:54 · 2 answers · asked by moosaur 2

need it for a project..plzzz help..im desperate

2007-12-08 06:02:34 · 3 answers · asked by animals1077 3

to move a large crate across a rough floor, you push on it with a force F at an angle of 21 degree below the horizontal. Find the force necesssary to start the crate moving, given that the mass of the crate is 32 kg and the coefficient of static friction between the crate and the floor is 0.57

2007-12-08 05:37:03 · 2 answers · asked by Anonymous

An organ pipe open at both ends has a radius of 6.0cm and a length of 4.0m. If the temperature is 20C, what is the fundamental frequency of the organ pipe?

2007-12-08 05:31:00 · 2 answers · asked by limeinelcoconut 1

9.
*A transformer has 200 turns on the primary and 20 turns on the secondary. The primary is connected to a direct current source of 100 millivolts. The voltage in the secondary coil will be

2007-12-08 05:03:43 · 1 answers · asked by Anonymous

a gardener mows a lawn with an old-fashioned push mower. The handle of the mower makes an angle of 32 degree with the surface of the lawn.
a) If a 209-N force is applied along the handle of the 18-kg mower, what is the normal force exerted by the lawn on the mower?
b) If the angle between the surface of the lawn and the handle of the mower is increased, does the normal force exerted by the lawn increase, decrease, or stay the same?

2007-12-08 04:30:27 · 2 answers · asked by Anonymous

2007-12-08 04:22:24 · 4 answers · asked by k k 2

2007-12-08 03:04:58 · 2 answers · asked by navya 1

2007-12-08 02:59:30 · 2 answers · asked by alex n 2

Io, a satellite of Jupiter, has an orbital period of 1.77 days and an orbital radius of 4.22 * 10^-5 km. From these data, determine the mass of Jupiter.

How would I go about doing this. Don't tell me the answer, just the process, please.

2007-12-08 02:56:48 · 4 answers · asked by Muffins 1

2007-12-08 02:51:16 · 5 answers · asked by daballer_atlanta 1

2007-12-08 02:50:44 · 3 answers · asked by Anonymous

2007-12-08 02:45:13 · 2 answers · asked by Anonymous