Doubt from PYQ physics


In second one, why is A not the ans?

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Because it’s given that magnitude of positive charge density is greater than magnitude of negative charge density

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3.3 * 3 * 10^-4 * 1/2 = 5 * 10^-4 should be the answer. Polarizer is rotating so we take average of cos² theta which is 1/2.

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yeh wala fiitjee aits me tha

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I guess that is energy per sec.
To find energy per revolution, we’ll need to multiply further by its time period, right?

Wait :thinking:… I’m more confused you already took: I• cos² x and got average value for x=0 to x= 360 as I/2 :sweat:

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Nope, energy is constant and passing through the polarizer and only the angle is changing, so we E/2 will do it.

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Its taking a lot to process this :sweat: I’ll just go with you :sweat_smile:

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this is from I=Icos^2theta (Malus Law right)

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Right. For unpolarized light passing through a polarizer or a plane polarized light passing through a rotating polarizer intensity becomes half (average of cos²theta)

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Then for unpolarized light passing through rotating polarizer it will be 1/4 Io na?

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Can’t say. Unpolarized light me EF ke variation boht saari direction me hoga and polarizer bhi rotate karega toh har direction me liye angle alag hoga. Aise directly 1/4 nahi kar sakte shayad.

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Hmmm… Ye bhi baat shi h

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Does anyone have any theory portion related to mutimeter?if then plz share

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multimeter is just a device to measure voltage, current, and resistance, it looks like a calculator and has a screen which shows the three quantities, divides in with its computer so you don’t have to. it can also kill you if you put on end on your wrist, slightly embedded and put the other end in your hand, it will result in immediate death. just prick your thumb a little bit, you’ll get some blood now complete the circuit and RIP.

but on a serious note if you are talking about this questionScreenshot 2021-02-22 at 5.25.58 PM

since there is a little bit of resistance it means the transistor is forward bias. R is negative and P/Q is positive that mean R has to be the collector so its an npn.

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Ye kya tha :joy::joy::joy::joy::joy::joy: i was seriuosly trying to understand :rofl::rofl:

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Ye samjha do koi ye kaun se logic gates hai

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AND gate h ye

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Thoda confusion ho gaya tha , And Gate mujhe ajeeb lag raha tha

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Ye kisko represent kar raha hai kaise pata kare

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options thode dicey hai… galat hai 1st mien typo hai

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