Author Topic: physics  (Read 19176 times)

Offline Phosu

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Re: physics
« Reply #60 on: March 27, 2010, 04:44:15 pm »
a and b both equal to 1/4A

Offline ruby92

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Re: physics
« Reply #61 on: March 27, 2010, 04:47:18 pm »
:S:S
wht did i do wrong???

Offline Phosu

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Re: physics
« Reply #62 on: March 27, 2010, 04:56:31 pm »
uh you didn't read my explanation, because i have stated your mistake in there...

Offline ruby92

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Re: physics
« Reply #63 on: March 27, 2010, 05:03:29 pm »
 :-[ sorry
ok soo why is Ic =Ia+Ib
???are a and b going out of the junction?

Offline ruby92

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Re: physics
« Reply #64 on: March 27, 2010, 05:12:27 pm »
Two loudspeakers both emit sounds with a frequency of 340Hz. Both sounds have equal amplitude and phase. The amplitude is A. The speakers are 4m apart and face each other. (The speed of sound in air is 340ms-1)

a) What is the wavelength of the sound?

 0.5m
 1m
 1.5m
 2m
b) Ignoring the reduction of amplitude with distance from each speaker, what is the amplitude of the sound;

i) halfway between the speakers?

 0
 1 A
 2 A
 3.142 A
ii) 0.5m from either speaker?

 0
 1 A
 2 A
 3.142 A
iii) 1m from either speaker?

 0
 1 A
 2 A
 3.142 A

Offline Phosu

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Re: physics
« Reply #65 on: March 27, 2010, 05:25:34 pm »
:-[ sorry
ok soo why is Ic =Ia+Ib
???are a and b going out of the junction?
if you complete the loop of both Ia and Ib you will find that they both meet up before entering the 3ohm resistor.
so Ia+Ib=Ic

i guess the going out part was just to create confusion

Offline halosh92

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Re: physics
« Reply #66 on: March 27, 2010, 05:27:52 pm »
Two loudspeakers both emit sounds with a frequency of 340Hz. Both sounds have equal amplitude and phase. The amplitude is A. The speakers are 4m apart and face each other. (The speed of sound in air is 340ms-1)

a) What is the wavelength of the sound?

 0.5m
 1m
 1.5m
 2m
b) Ignoring the reduction of amplitude with distance from each speaker, what is the amplitude of the sound;

i) halfway between the speakers?

 0
 1 A
 2 A
 3.142 A
ii) 0.5m from either speaker?

 0
 1 A
 2 A
 3.142 A
iii) 1m from either speaker?

 0
 1 A
 2 A
 3.142 A

which paper is this?
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline ruby92

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Re: physics
« Reply #67 on: March 27, 2010, 05:48:23 pm »

Offline halosh92

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Re: physics
« Reply #68 on: March 27, 2010, 06:14:30 pm »
this is from this website
http://www.acoustics.salford.ac.uk/feschools/waves/super.htm

the first part its 1m
 all the other parts have the same amplitude
but which amplitude i have no idea
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline ruby92

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Re: physics
« Reply #69 on: March 27, 2010, 06:34:19 pm »
its 2A then 0A then 2 A

Offline ruby92

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Re: physics
« Reply #70 on: April 19, 2010, 08:24:13 pm »
A car of mass 1000kg pulls a mass of 800kg,The driver wants to speed up with an acceleration of 2ms-2.with what force must the car pull the mass?what motive force must the engine provide?

nid404

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Re: physics
« Reply #71 on: April 19, 2010, 08:25:57 pm »
F=ma
F=1800X2=3600N

yaa?

Offline Saladin

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Re: physics
« Reply #72 on: April 19, 2010, 08:45:37 pm »
F=ma
F=1800X2=3600N

yaa?

That is correct if you assume that the tension is unifor in the rod connecting the two, and it is paralell to the ground.

Offline T.Q

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Re: physics
« Reply #73 on: April 19, 2010, 11:30:46 pm »
its 2A then 0A then 2 A

the answer is 0A THEN 0A THEN 0A
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nid404

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Re: physics
« Reply #74 on: April 20, 2010, 07:09:59 am »
That is correct if you assume that the tension is unifor in the rod connecting the two, and it is paralell to the ground.

I guess cuz nothing's mentioned in the question