Quantrex Academy Quantrex AcademyPYQs with solutions · JEE · NEET · NDA

Home · JEE Main & Advanced · Physics · Photometry

Photometry — JEE Main & Advanced Physics PYQs

40 previous year questions from Photometry with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

40 questionsPhysicsSolutions on every page
1

Calculate the radiant flux of a source if it emits 45 joules of energy over a period of 15 s .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 2

When exposed to a 10 W source for 12 s , a photographic plate records sufficiently intense lines. To obtain equally intense lines, what should be the exposure time for a 12 W sourc

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 3

Based on the relative luminosity curve shown in the figure, determine the relative luminosity of wavelength 580 nm .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 4

Based on the relative luminosity curve shown in the figure, determine the relative luminosity of wavelength 520 nm .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 5

Based on the relative luminosity curve shown in the figure, determine the relative luminosity of wavelength 600 nm .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 6

The relative luminosity for a wavelength of 600 nm is 0.6 . Determine the radiant flux at 600 nm required to generate the same brightness sensation as that produced by a radiant fl

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 7

Based on the relative luminosity curve shown in the figure, determine the relative luminosity of wavelength 480 nm .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 8

A monochromatic source of 1 W produces a luminous flux of 450 lumen . Determine the relative luminosity at the emitted wavelength.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 9

A source emits light of wavelengths 555 nm and 600 nm . The radiant flux of the 555 nm part is 40 W while that of the 600 nm part is 30 W . The relative luminosity at 600 nm is 0.6

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 10

A source emits light of wavelengths 555 nm and 600 nm . The radiant flux of the 555 nm part is 40 W while that of the 600 nm part is 30 W . The relative luminosity at 600 nm is 0.6

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 11

A source emits light of wavelengths 555 nm and 600 nm . The radiant flux of the 555 nm part is 40 W while that of the 600 nm part is 30 W . The relative luminosity at 600 nm is 0.6

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 12

A light source produces monochromatic light of wavelength 555 nm . It consumes 100 W of electric power and emits 35 W of radiant flux. Compute the overall luminous efficiency.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 13

A source uniformly radiates 31.4 W of radiant flux in all directions. If the luminous efficiency is 60 lumen watt ⁻¹ , determine the luminous intensity of the source.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 14

A point source, positioned at the origin, emits 628 lumen of luminous flux uniformly in all directions. Determine the illuminance on a small area located at (1.0 m , 0, 0) , given

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 15

The illuminance of a small area changes from 900 lumen m ⁻² to 400 lumen m ⁻² when it is shifted by 10 cm along its normal. Assuming illumination by a point source positioned on th

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 16

A point source emitting light uniformly in all directions is situated 60 cm above a table-top. At a point on the table-top directly beneath the source, the illuminance is 15 lux .

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 17

Light from a point source strikes a small area oriented perpendicular to the incident light. If the area is rotated by an angle of 60^ about the incident light, by what fraction wi

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 18

A student is reading a book located near the edge of a circular table of radius R . A point source of light is suspended directly above the centre of the table. Determine the heigh

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 19

As illustrated in the figure, a small diffused plane source S is positioned 2.4 m above a horizontal table-top, such that its plane is parallel to the table-top. At point A , which

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 20

When positioned at 80 cm and 20 cm from a photometer screen respectively, an electric lamp and a candle generate equal illuminance. The lamp is subsequently covered with a thin pap

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 21

Two light sources having intensities of 8 cd and 12 cd are positioned on the same side of a photometer screen, at a distance of 40 cm from it. At what distance must an 80 cd source

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 22

When the wavelength is increased from violet to red, the luminosity

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 23

Three light sources A , B , and C emit an identical amount of radiant energy per unit time. The wavelengths produced by the three sources are 450 nm , 555 nm , and 700 nm , respect

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 24

An electric bulb is suspended over a table at a height of 1 m . The illuminance on the table directly beneath the bulb is 40 lux . The illuminance at a point on the table located 1

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 25

Light originating from a point source strikes a screen. If the separation between the source and the screen is increased by 1 % , the illuminance decreases by approximately

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 26

At a small distance r from a long cylindrical light source, the intensity produced is proportional to

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 27

The single parameter that dictates the brightness of a light source perceived by an eye is

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 28

When positioned 5 cm away from a weak point source, a photographic plate requires an exposure time of 3 s . If the plate is instead located at a distance of 10 cm from the source,

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 29

A photographic plate is positioned directly in front of a small diffused source shaped as a circular disc. Obtaining a good exposure takes 12 s . If the source is rotated by 60^ ar

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 30

A point source of light travels in a straight line parallel to a plane table. Consider a small portion of the table directly beneath the line of motion of the source. The illuminan

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 31

The figure displays a glowing mercury tube. The intensities at points A , B , and C are related by

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 32

A battery-operated torch is configured to emit an almost parallel beam of light. When the light strikes a wall 2 m away, it produces an illuminance of 40 lux . The illuminance prod

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 33

Identify the correct statements from the following.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 34

Select the correct options from the following.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 35

An extended source illuminates a room. The illuminance at a specific section of a wall can be enhanced by

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 36

The brightness-producing capability of a source

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 37

Identify the correct statements from the following.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 38

Select the correct options from the following.

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 39

An extended source illuminates a room. The illuminance at a specific section of a wall can be enhanced by

Concepts Of Physics MCQ Edition [Volume 1] Solution View → 40

The brightness-producing capability of a source

Concepts Of Physics MCQ Edition [Volume 1] Solution View →
Practice all Photometry questions in the app →