MyQuestionIcon

4

You visited us 4 times! Enjoying our articles? Unlock Full Access!

Blackbody

In the above ...

Question

In the above problem, the luminance of blotting paper is

A

3

phot

No worries! We‘ve got your back. Try BYJU‘S free classes today!

B

3

lux

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

C

4

phot

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

4

lux

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B $3$ lux
The source of luminance of the blotting paper is the light reflected by it. Since 75 % of light is reflected,

luminance = $\frac{100}{5^{2}} \times \frac{75}{100}$ = 3 lux

Answer. B) 3 lux

Suggest Corrections

thumbs-up

0

Similar questions

Q. An electric bulb is hanging over a table at a height of 1 m above it. The illuminance on the table directly below the bulb is 40 lux. The illuminance at a point on the table 1 m away from the first point will be about
(a) 10 lux
(b) 14 lux
(c) 20 lux
(d) 28 lux

Q. A battery-operated torch is adjusted to send an almost parallel beam of light. It produces an illuminancle of 40 lux when the light falls on a wall 2 m away. The illuminance produced when it falls on a wall 4 m away is close to
(a) 40 lux
(b) 20 lux
(c) 10 lux
(d) 5 lux

Q. Lux is the unit of :

Q. The illuminance of a surface distance

10

m from a light source is

10

lux. The luminous intensity of the source for normal incidence will be

Q. Out of the following, select Lux-Flood Acid.

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Radiation

PHYSICS

Watch in App

explore_more_icon

Explore more

Standard XII Physics

Join BYJU'S Learning Program

CrossIcon