Ray Optics Test

Result

Ray Optics Test - 152

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
4 / -1

\"Lux\" is a unit of

A
Luminous intensity of a source

B
Illuminance on a surface

C
Transmission coefficient of a surface

D
Luminous efficiency of source of light
Question 2
4 / -1

Total flux produced by a source of 1 cd is

A
1/4 π

B
8π

C
4π

D
1/8 π

Solution
Question 3
4 / -1

Lux is equal to

A
1 lumen/m²

B
1 lumen/cm²

C
1 candela/m²

D
1 candela/cm²

Solution
Question 4
4 / -1

Five lumen/watt is the luminous efficiency of a lamp and its luminous intensity is 35 candela. The power of the lamp is

A
80 W

B
176 W

C
88 W

D
36 W

Solution
Question 5
4 / -1

A lamp rated at 100 cd hangs over the middle of a round table with diameter 3 m at a height of 2 m. It is replaced by a lamp of 25 cd and the distance to the table is changed so that the illumination at the centre of the table remains as before. The illumination at edge of the table becomes X times the original. Then X is

A
1/3

B
16/27

C
1/4

D
1/9

Solution
Question 6
4 / -1

The distance between a point source of light and a screen which is 60 cm is increased to 180 cm. The intensity on the screen as compared with the original intensity will be

A
(1/9) times

B
(1/3) times

C
3 times

D
9 times

Solution
Question 7
4 / -1

A source of light emits a continuous stream of light energy which falls on a given area. Luminous intensity is defined as

A
Luminous energy emitted by the source per second

B
Luminous flux emitted by source per unit solid angle

C
Luminous flux falling per unit area of a given surface

D
Luminous flux coming per unit area of an illuminated surface
Question 8
4 / -1

Venus looks brighter than other stars because

A
It has higher density than other stars

B
It is closer to the earth than other stars

C
It has no atmosphere

D
Atomic fission takes place on its surface

Solution
Question 9
4 / -1

To prepare a print the time taken is 5 sec due to lamp of 60 watt at 0.25 m distance. If the distance is increased to 40 cm then what is the time taken to prepare the similar print

A
3.1s

B
1 s

C
12.8 s

D
16 s

Solution
Question 10
4 / -1

A lamp is hanging lm above the centre of a circular table of diameter lm. The ratio of illuminaces at the centre and the edge is

A

B

C

D

Solution