Help please!!

Hello Brilliantians!

Please help me with question number 11 & 12.

Also suggest any good book or website for studying geometrical optics.

Thanks!

#Mechanics #Opti

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Comments

For question 11, there is missing information. All the options are possible.

For question 12, no image should be formed.

The second black line is the concave lens.

The red lines, or the rays of light, would diverge upon hitting the concave lens, and the rays would not intersect again. Since in order for another image to be formed after the light hit the concave lens, the 2 rays of light has to intersect, there would be no image formed.

Julian Poon - 5 years, 8 months ago

11th Question's answer is 6 cm.

CH Nikhil - 5 years, 7 months ago

Please explain .

Harsh Shrivastava - 5 years, 7 months ago

Tomorrow.

CH Nikhil - 5 years, 7 months ago

@Tanishq Varshney @Chew-Seong Cheong @Kalash Verma @Aditya Kumar @Surya Prakash

Harsh Shrivastava - 5 years, 8 months ago

11:-2.25 ?

Department 8 - 5 years, 8 months ago

I don't know the answer... Anyways how did you reached till there?

Harsh Shrivastava - 5 years, 8 months ago

@Harsh Shrivastava – Oh sorry, I thought it was convex mirror, wrong answer (Seriously sorry).

Department 8 - 5 years, 8 months ago

I feel that the 11th question is incomplete.

Aditya Kumar - 5 years, 8 months ago

This is quite good, as are most Schaum's problem books:

Josh Silverman Staff - 5 years, 8 months ago

Thanks sir!

BTW can you help me with question no. 11 & 12?

Harsh Shrivastava - 5 years, 8 months ago

11- 6cm 12 - shifts away from the lens system

rishabh singhal - 5 years, 6 months ago

Hints for 11 which should be enough to solve it.

Note that linear magnification of a lens is given by $\large \frac{v}{u}$ . Linear magnification is length of image divided by length of object.
The second crucial thing to note is that focal length remains unchanged in both the cases. Note that $\large \frac{1}{f} = \frac{1}{v} - \frac{1}{u}$ .

Pulkit Gupta - 5 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$