Question

two lens of power + 2.5 diopter and -3.75 dauter are combined to form a compound lens its focal length in cm will be​

Answer 1

Answer:

If it helps mark me as brainliest.

Explanation:

Total power

=( 2.5-3.75)D

= -1.25

So, required focal length

=

$\frac{1}{ - 1.25} \\ = - \frac{100}{125} \\ = - \frac{4}{5} \\ = - 0.8m \\ = 80 \: cm$

Answer 2

Answer:

The answer is 40

I hope this answer is correct