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ALL CIE PHYSICS DOUBTS HERE !!!
Hypernova:
--- Quote from: Dania on November 06, 2010, 05:10:56 pm ---Okay, so I seem to be stuck on (b) [Refer to the attachment]. Would I use the equation "Phase angle = 2(pie)x/lambda"?
--- End quote ---
I don't know the DK's method, hopefully, he'll explain it to you.
This is what i do.
First find the amplitude of the second waveform.
We know that the intensity of the second wave is doulde the first,
So, 2I1=I2
Intesity is proportional to amplitude2
I1=K x 52 I2= K x a2
K=I1/52 K= I2/a2
now equate the two Ks
I1/52 = I2/a2
using 2I1=I2, we say: 2= I2/I1
I1/52 = I2/a2
I2/I1 = a2/25
2 = a2/25
50 = a2
a = 7
Now draw the graph.
See I just know how to draw the graph. If the Wave has a hase difference of 180 degress, then it is completely out of phase,
If it is 90, then a 0.25 out of phase.
In other words. Look at the graph they gave you, 0.6 is one wavelength. So from 0 to O.6 is 360 degrees. so at 0.3, the phase angle of that point is 180 degrees. The new wave, when it starts from 0, will be in phase with the wave at this point.
So my wave looks like the one attached.
$!$RatJumper$!$:
All that work for 2 marks :( wow Cambridge sucks lol
$!$RatJumper$!$:
W03 P2 Q 3 (c) (ii) 2, why is the torque the same as the moment? I thought torque was calculated by the equation:
Torque = Force * Perp Distance between two forces
Hypernova:
Torque and moment is essentially the same, both being the turning effect of a force
a 'moment' is called 'torque' when it involves a couple.
Look at this
Torque = Force * Perp Distance between two forces
Torque= Force x (Perp Distance between pivot x 2)
Torque= 2 x Force x Perp Distance between pivot
Moment = Force1 x Perp Distance between pivot + Force2 x Perp Distance between pivot (Since F1=F2)
Moment= 2 x Force x Perp Distance between pivot
There is no difference bettween them, just the definition.
$!$RatJumper$!$:
--- Quote from: Hypernova on November 07, 2010, 12:30:46 pm ---Torque and moment is essentially the same, both being the turning effect of a force
a 'moment' is called 'torque' when it involves a couple.
Look at this
Torque = Force * Perp Distance between two forces
Torque= Force x (Perp Distance between pivot x 2)
Torque= 2 x Force x Perp Distance between pivot
Moment = Force1 x Perp Distance between pivot + Force2 x Perp Distance between pivot (Since F1=F2)
Moment= 2 x Force x Perp Distance between pivot
There is no difference bettween them, just the definition.
--- End quote ---
Thank you :) that makes a lot of sense :)
Another question, S04 Q 4 (b)(i), what is the direction of the force?
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