1. Visible spectrum of the light has a wavelength in the range of:

A. 1000 to 4000 Ao 
B. 4000 to 7000 Ao 
C. 7500 to 12500 Ao 
D. 12500 to 30000 Ao

Answer: (B)

2. Luminous flux is:
A. The rate of energy radiation in the form of light waves 
B. The part of light energy radiated from light source
C. Measured in Lux 
D. Both a and c

Answer: (A)

3 . Candela is the unit of:
A. Illumination 
B. Luminous intensity 
C. Luminance 
D. Light energy

Answer: (B)

4. Sky appears to be blue because of:
A. Radiation of light over dust particles 
B. Reflection of light over dust particles
C. Refraction of light over dust particles 
D. Scattering of light over dust particles

Answer: (D)

5. Candle power is:
A. The luminous flux emitted by the source per unit solid angle
B. The part of the light energy radiated by the sun that is received by earth
C. Measured in Lux
D. None of the above

Answer: (B)

6. An object which appears to be red to the eyes absorbs:
A. Blue radiation 
B. Violet radiation
C. Green radiation 
D. Absorbs all the above radiation

Answer: (D)

7. Which of the following colour has the wavelength between blue and yellow:
A. Violet 
B. Orange 
C. Red 
D. Green

Answer: (D)

8. Which of the materials is most commonly used for the filaments in the incandescent lamps:
A. Tungsten 
B. Tin 
C. Silver 
D. Asbestos

Answer: (A)

9. The expected life of an incandescent lamp is about:
A. 100 hours 
B. 200 hours 
C. 500 hours 
D. 1000 hours

Answer: (D)

10. ‘Camera’ is actually a Latin word meaning
A. picture box 
B. room 
C. light box 
D. none of the above

Answer: (B)