The diagram of the human excretory system is given below. Select theoption that correctly shows the functions of parts 'a' and 'b'.
a - Formation of urine, b - Collection of urine
a - Formation of urine, b - Carrying urine for storage
a - Formation of urine, b - Throwing urine outside the body
a - Collection of urine, b - Formation of urine
Magnification produced by a lens is equal to:
\( \frac{u}{v} \)
\( \frac{-v}{u} \)
\( \frac{v}{u} \)
\( \frac{-u}{v} \)