Illumination Objective Questions

___________________________ factor is defined as the ratio of the illumination when everything is clean to illumination under normal working conditions.

Which of the following statement is correct?

Luminous efficiency of a fluorescence lamp is

The unit of solid angle is

Candela is the unit of

ψ Wave length for red colour is

Solid angle is expressed in terms of

The illumination of the surface varies directly with cosine of the angle between normal to surface and direction of the inclined light is given by

In illumination technology total lumens emitted by source / total lumens available after waste of light is equal to

Carbon arc lamps are commonly used in

Total flux or lumens required in any lighting scheme depends inversely on

Candela is the unit of which?

Illumination can be expressed in

The solid angle subtended by an area of 2400 cm² on the surface of a sphere of diameter 1.2 m is

A solid angle can be expressed in terms of

A 200 candle power lamp is hung 4 m above the centre of circular area of 5 m diameter. The illumination at centre of the area is

What will be the total flux emitted by a source of 60 candle power?

From a uniform light source of 300 c.p. there exists a plane surface 15 m below the value of illumination on the plane surface when the luminous flux rays are inclined at an angle of 30 to the surface is

Radiant efficiency of the luminous source depends on

Unit of luminous flux is