On passing through food stuff, X-ray can kill the _____.

1. 1. Insects
   2. Virus
   3. Bacterials
   4. Fungus

Soldiers crossing a suspension bridge, always break steps, incase the frequency of vibration of their marching should coincide with that of the bridge and this is because of the phenomenon of:

1. 1. Resonance of sound
   2. Refraction of sound
   3. Echolocation of sound
   4. Reverberation of sound

Sound travels faster in _____.

1. 1. Dry air than in water
   2. Hydrogen than in water
   3. Iron than in air
   4. Wood than in iron

Electromagnetic waves travel with the _____.

1. 1. Speed of light
   2. Speed of earth rotation
   3. Speed of sun rotation
   4. Speed of sound

When light enters from rare to denser medium, it bends towards the normal line, it is called _____.

1. 1. Absorption of light
   2. Refraction of light
   3. Diffraction of light
   4. Reflection light

Argon laser is used for operating the _____.

1. 1. Kidney stone
   2. Eye cance3r
   3. Bone disease
   4. Glaucoma

For making laser, usually we use _____.

1. 1. Iron
   2. Ruby
   3. Magnesium
   4. Uranium

The device which converts analogue signal to digital signal is called _____.

1. 1. Modem
   2. CPU
   3. Photodiode
   4. Transformer

In Binary system, the figure 361 is written as _____.

1. 1. 10101101
   2. 10110111
   3. 1001101
   4. 101101001

A.C. voltage is _____.

1. 1. Analogue quantity
   2. Chemical quantity
   3. Digital quantity
   4. Mathematical quantity