Question

..............Q 11..............​

Answer 1

case 1

m=-v/u

-1=-(-30)/u

u= -30 cm

case 2

image will form behind the mirror

it'll be virtual and erect

Answer 2

HERE IS YOUR ANSWER. ...


The ability of a lend to converge or diverge the light rays is called power of a lens.

for lens L₁   P₁=+10D

Since the power is positive the nature of the lens is converging

f₁=1/P₁   f₁=1/10   f₁=0.1m     f₁= +10cm

For lens L₂   P₂=+5D

since the power is positive the nature of the lens is converging

f₂=1/P₂       f₂=1/+5     f₂=0.2m   f₂ =20cm

For lens L₃     P₃= -10D

Since the power is negative the nature of the lens is diverging in nature

f₃= 1/P₃    f₃=1/-10    -0.1m      f₃= -10cm

Lens L₂ will produce virtual erect and enlarged or magnified image because the distance of the object is less than focal length .or the object lies between the optical center and Principal focus.

L₁ will not produce a virtual erect and enlarged image because the object lies between F₁ and 2F₁

L₃ being diverging in nature i.e a concave lens it always produces a virtual erect and diminished image of the object.

HOPE IT HELPS YOU! ! ! ! ! !