Question

26. A concave mirror and a converging lens (glass
with u =: 1.5) both have a focal length of 3 cm
when in air. When they are in water of refractive index 4/3their new focal lengths are
a) lens = 12 cm. Mirror = 3cm
(b) lens = 3 cm. Mirror = 12cm
(c) lens - 3 cm. / Mirror = 3cm
(d) lens = 12 cm. Mirror = 12cm
​

Answer 1

$\boxed{\bf{\blue{\longrightarrow Answer:}}}$

• Focal length of mirror doesn't change with media
• Focal length of convex lens is 1.5 and water is 1.33
• As the The R. I of water is less then convex lens it will continue behaving like convex lens only
• So Option (C) is correct
• Both Focal lengths will remain same

Answer 2

Answer:

B) it will be 3cm and 12, cm

Explanation:

thanks :-)