Physics - March 2007

A bath contains 100kg of water at 60 degree celsius. Hot and cold taps are then turned on to deliver 20kg per minute each at temperatures of 70 degree celsiuys and 10 degree celsius respectively. How long will it be before the temperature in the bath has dropped to 45 degree celsius?

Assums complete mixing of water and ignore heat lossses.

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I'd appreciate detailed working please. I assure you that best answer will be chosen!

2007-03-17 16:43:02 · 3 answers · asked by Chocolate Strawberries. 4

The temperature of a brass cylinder of mass 100g was raised to 100 degree celsius and then transferred to a thin aluminium can of negligible heat capacity. The aluminium can contained 150g of paraffin at 11 degree celcius. If the final steady temperature after stirring was 20 degree celsius, claculate the specific heat capacity of paraffin

(Neglect heat losses, and assume specific heat capacity of brass= 38 J/gK

2007-03-17 16:17:12 · 2 answers · asked by Chocolate Strawberries. 4

a ball is traveling at a constant velocity of 50m/s and has been
traveling for 2 minutes, what is the ball's acceleraton.

2007-03-17 16:15:08 · 5 answers · asked by Anonymous

Why do we hold on the the hair when electrified? what's in the hair?

2007-03-17 16:04:54 · 3 answers · asked by ave angelo b 1

A gymnast is performing a floor routine. In a tumbling run she spins through the air, increasing her angular velocity from 3.00 to 4.00 rev/s while rotating through three-fourths of a revolution. How much time does this maneuver take?

2007-03-17 16:03:33 · 2 answers · asked by Anonymous

2007-03-17 15:54:54 · 2 answers · asked by chocol8coatedbutterfly 1

has there been any empirical evidence to support this notion or is it proven in equations only?

2007-03-17 15:38:17 · 2 answers · asked by Anonymous

Hey everyone... i'm stuck on two problems.. if anyone could help me out that would be great... thanks in advance!

A conducting sphere radius R has a total charge of Q on its surface, how much charge will there be on this sphere's surface after it is brought into contact with another, initially uncharged conducting sphere of radius 2R?

and...

A conducting sphere of radius R with a charge Q on its surface and a potential V inside is brought into contact with another initially uncharged conducting sphere of radius 4R. After reaching equillibrium, the potential inside the larger sphere becomes?

2007-03-17 15:33:28 · 1 answers · asked by Anonymous

Problems: http://img410.imageshack.us/img410/6060/scalepi6.gif
These are probably trivial but I have no idea how they are derived to the point of solution

2007-03-17 15:18:32 · 2 answers · asked by sotkinghunter 1

For my science homework my teacher asks. "what is the cause of an electrical charge and of magnetism?"

2007-03-17 14:50:37 · 3 answers · asked by vince 2

2007-03-17 14:45:55 · 4 answers · asked by Anonymous

The force that holds us on earth, where does it come from? what causes it? james

2007-03-17 14:43:29 · 10 answers · asked by james h 2

I've been told Turning ON a light uses more electricity than actually Leaving the light on. Is that true?

2007-03-17 14:40:51 · 8 answers · asked by nitapoop 1

a)higher in the water
b)lower in th ewater
c)at the same water level

2007-03-17 14:09:16 · 7 answers · asked by cesar i 1

a)areas
b)radii
c)diameters
d)all of these
e)none of these

2007-03-17 13:59:57 · 3 answers · asked by cesar i 1

ok so around 3 o clock today my brother. my grandpa and i heard a loud crashing noise. about 10 mins ago my brother went into his bathroom to discover what the noise was. The lightbuld above the sink had some how fallen into the sink and totally shattered....


how is it possible for the lightbulb to just randomly fall out of its little socket thing???

2007-03-17 13:59:38 · 3 answers · asked by lala l 1

which way would it fall? or would it just float there?

2007-03-17 13:54:09 · 4 answers · asked by wrldzgr8stdad 4

According the Heisenberg's uncertainty principle, the BBs do not fall straight down from the release point to the center of the bullseye, but are affected by the initial conditions. a)if the location point is uncertain by an amount ^x=0.1mm in the horiz. direction, calculate the miniumum spread ^X of the impacts. b) If there is an uncertainty ^y=0.1mm in the release point, what is ^X? c)Would this affect your darts game accuracy?

2007-03-17 13:52:29 · 2 answers · asked by Joshua R 1

a)double
b)saty the same
c)halve
d)become four times as great

2007-03-17 13:51:11 · 4 answers · asked by cesar i 1

I'm doing a project for physics and I can't think of any more examples of physics in everyday life.
Not too complex please, I'm looking for things like waves on a beach (Simple Harmonic Motion), or night vision, binoculars, microscopes, ect...
Be as abstract as you like, thanks.

2007-03-17 13:25:46 · 6 answers · asked by Brian 3

a)rises
b)falls
c)remains unchainged

2007-03-17 13:17:01 · 8 answers · asked by cesar i 1

If E=MC^2, where E = energy, M=mass, C=speed of light, how can photons have energy if they are massless?
(M=zero) x C^2 = zero

2007-03-17 12:51:16 · 6 answers · asked by Raymond 2

I need to know this by Tuesday please

2007-03-17 12:26:31 · 4 answers · asked by Delwyn G 2

2007-03-17 12:04:14 · 3 answers · asked by NG KW 1

Huh, nerds... what is it?

2007-03-17 11:50:50 · 7 answers · asked by The Don 1

I want to produce a frequency of 83.5 kilohertz, but all of the signal generators I have found that can produce in that range are very expensive. Can anyone tell me what type of circuit I could use to make a very precise frequency like that and, if you can, where I can find a diagram for it on the web?

2007-03-17 11:46:03 · 3 answers · asked by metaphysics1221 2

Most people have discussed the importance of scientific advancements in the 20th century like cloning, in space etc but the question that always comes in to my mind is why was the rate so fast in the past century and why not in earlier centuries even though there were genius people like Einstein around. I don’t intend to deny the advancements that took place but no one ever discusses the reason for them I have looked around a lot of places but never got a satisfactory answer! The question still bothers me.

2007-03-17 11:31:59 · 4 answers · asked by daniel 1

im 16,and looking for a career, im okay at math and logic,but nowhere near genius level, astrophysics has always fascinated me though! can i realistically be successful as an astrophysicist? i'd prefer if answerers actually did it in college, or had some experience of what its like.

2007-03-17 11:25:58 · 4 answers · asked by Loki 1

2007-03-17 10:49:03 · 3 answers · asked by hadeelysaid 1

How long will the astronaut need to fire a 100.0 N rocket backpack to stop the motion relative to the spacecraft?

2007-03-17 10:33:50 · 5 answers · asked by Hannah 1