In displacement method we use a lens of focal length f and distance between object and screen is 60 cm. Possible value for focal length is

Question

In displacement method we use a lens of focal length f and distance between object and screen is 60 cm. Possible value for focal length is (A) -15 cm (B) 30 cm (C) 12 cm (D) 20 cm

Tardigrade Admin · Accepted Answer

f ≤ (D/4) f ≤ (60/4) f ≤ 15 cm

Q. In displacement method we use a lens of focal length $f$ and distance between object and screen is $60 c m$ . Possible value for focal length is

-15 cm

30 cm

12 cm

20 cm

$f \leq \frac{D}{4}$
$f \leq \frac{60}{4}$
$f \leq 15 c m$

Q. In displacement method we use a lens of focal length f and distance between object and screen is 60cm. Possible value for focal length is