TS EAMCET 04 May 2019 Shift 2 Solved Paper

The pass axes of two polarizer are kept in such a way that the incident unpolarized beam of intensity I0 gets completely blocked.
When third polarizer is introduced between the other two polarizer such that the angle between the pass axes of the first and third polarizes is 60∘, then the intensity of ploarised light emerging from first Polaroid is,

I1‌‌=‌

I0

2

‌ So ‌&
I3‌‌=I1cos2θ
‌‌=‌

I0

2

cos260∘
‌‌=‌

I0

2

(‌

1

4

)
‌‌=‌

I0

8

Now, the angle between pass axis of P3 and P2 is
θ2‌‌=90∘−60∘
‌‌=30∘
Therefore,
I2‌‌=I3cos2θ2
‌‌=(‌

I0

8

)cos230∘
‌‌=(‌

I0

8

)(‌

3

4

)
‌‌=(‌

3I0

32

)