a) -4D
b) -1/4D
c) -2D
d) -I/2D
2007-12-17 22:02:35 · 8 answers · asked by ♥aesu♥ 1 in Science & Mathematics ➔ Physics
The power of a lens is 1/focal length (measured in meters). So, 50 cm is 1/2 meter, so the power is -2; D stands for diopters, the unit of power for lenses.
2007-12-17 22:08:24 · answer #1 · answered by kuiperbelt2003 7 · 0⤊ 0⤋
A Concave Lens
2016-12-18 05:01:55 · answer #2 · answered by tsistinas 4 · 0⤊ 0⤋
Focal length of a concave lens is conventionally taken as negative.
Power = reciprocal of focal length.
= 1/(-50 x 10^-2) = -2 dioptre.
Power of a concave lens is its ability to diverge light rays. Draw the ray diagram for some parallel rays and it will be clear that, lesser the focal length greater the converging power.
2007-12-18 00:34:17 · answer #3 · answered by raj 2 · 0⤊ 0⤋
if the lense is concave , the power is negative. The power is related to length by the formula P = 1/f f in meters)
so the power is -1/0.5 = -2D
answer C
2007-12-18 00:41:05 · answer #4 · answered by maussy 7 · 0⤊ 0⤋
answer is c.
as focal length is inverse of focal length.
2007-12-17 22:22:00 · answer #5 · answered by Joshua 2 · 0⤊ 0⤋
-.5
2007-12-21 00:08:45 · answer #6 · answered by BIKRAM D 1 · 0⤊ 0⤋
b
2014-02-16 02:41:43 · answer #7 · answered by Ramasankar Roula 1 · 0⤊ 1⤋
p=1/f
50=0.5
p=1/0.5
-2D
c)
2007-12-18 00:40:23 · answer #8 · answered by scholar 1 · 0⤊ 0⤋