In an atomic explosion, enormous energy is released which is due to the _____.

1. 1. Conversion of chemical energy into nuclear energy
   2. Conversion of chemical energy into heat energy
   3. Conversion of mass into energy
   4. Conversion of neutrons into protons

Which of the following is good nuclear fuel?

1. 1. Plutonium-239
   2. Neptunium-239
   3. Uranium-238
   4. Thorium-236

Which of the following is used as a coolant in unclear reactors?

1. 1. Graphite
   2. Heavy water
   3. Cadmium
   4. Liquid sodium

Two cars, passing each other at high speed, are in danger of side swiping because _____.

1. 1. Of decrease in the velocity of air molecules between them
   2. Of decrease in air pressure in the space between them
   3. Increase n the velocity of air molecules between them
   4. Of the increase in air pressure int he space between them

Phenomenon of formation of three dimensional image by interference of two light beams from laser or other coherent sources of light is called _____.

1. 1. Radiography
   2. X-ray photography
   3. Optical photography
   4. Holography

Which one of the following statement is correct?

1. 1. Does not radiate heat but absorbs heat from the surrounding
   2. Does not radiate heat
   3. Radiates heat but absorbs more heat from the surrounding
   4. Radiates heat more than that absorbed by it form the surrounding

A needle smeared with vaseline when lowered slowly on the surface of water in a horizontal position appears to float. The phenomenon is an example of _____.

1. 1. Osmosis
   2. Surface tension
   3. Capillary action
   4. Archimedes principle

Rectifiers are used to convert _____.

1. 1. High voltage to low voltage
   2. Low voltage to high voltage
   3. DC to AC
   4. AC to DC

when water boils, its temperature _____.

1. 1. Begins to decrease
   2. Remains constant
   3. Begins to increase
   4. Fluctuates

During rusting _____.

1. 1. Iron gains weight
   2. Iron volatilizes
   3. Weight of iron remains unchanged
   4. Iron loses weight