Author Topic: physics  (Read 17881 times)

Offline neno

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Re: physics
« Reply #180 on: May 09, 2010, 06:14:08 pm »
in june 2004 wat formula did u use to find the velocity..i understand the part tht ur resolving ur finding the vertical component of velocity ryt

r u using the formula 2as=v2-u2 do u take u2 at 0
                             2as=v sin theta
but y do u take 2 theata??

nid404

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Re: physics
« Reply #181 on: May 09, 2010, 06:20:14 pm »
you don't need the derivation

s= v2 sin 2\theta / g

Offline neno

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Re: physics
« Reply #182 on: May 09, 2010, 06:28:38 pm »
in octnov 2004 Q25 y cant it b the frequency cuz then v already noe the speed of sound n v cud jst simply devide..
lol i got Q33 when i read it 2wice
 Thanks alot By the way

Offline neno

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Re: physics
« Reply #183 on: May 09, 2010, 06:32:07 pm »
s= v2 sin 2 / g


v nvr used this formula so wat are the conditions tht u use it under
when thrs in angle or it requires more

is it used in projectiles also when u wana find the velocity ??

Offline halosh92

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Re: physics
« Reply #184 on: May 09, 2010, 08:01:09 pm »
in octnov 2004 Q25 y cant it b the frequency cuz then v already noe the speed of sound n v cud jst simply devide..
lol i got Q33 when i read it 2wice
 Thanks alot By the way

i believe thats because its a stationary wave
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline neno

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Re: physics
« Reply #185 on: May 10, 2010, 05:15:56 pm »
so the speed of a stationary wave is not the same as a progressive wave...but everything else is the same ryt the wavelength and the frequency....

Offline Phosu

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Re: physics
« Reply #186 on: May 11, 2010, 12:21:04 pm »
28 Microwaves of wavelength 3.00 cm are incident normally on a row of parallel metal rods. The separation of the rods is 8.00 cm. The first order diffraction maximum is observed at an angle of 22.0° to the direction of the incident waves.

What is the angle between the first and second order diffraction maxima?
A 22.0° B 26.6° C 44.0° D 48.6°

Offline astarmathsandphysics

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Re: physics
« Reply #187 on: May 11, 2010, 12:29:12 pm »
Strange question
28 microwaves?
Where is the question from

Offline Phosu

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Re: physics
« Reply #188 on: May 11, 2010, 12:34:15 pm »
nov 03 pp1,
i also have a few more doubts
4, 6, 14, 16,

Offline vanibharutham

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Re: physics
« Reply #189 on: May 11, 2010, 12:34:23 pm »
d sin(theta) = n Lamba

for the first order maxima, i.e. the central maxima

8 sin (theta) = 3 x 1

Theta = 22.04

confirmed :)

For the second order maxima,

8 sin (theta) = 2 x 3

theta = 48.6

therefore, the angle between them is

48.6 - 22 = 26.6

Therefore B
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