The spherical shape of a small drop of rain is due to _____.

1. 1. Viscosity
   2. Surface tension
   3. Atmospheric pressure
   4. Gravity

Which of the following devices is used to step up or step down the voltage of alternating current?

1. 1. Induction coil
   2. Transformer
   3. Transistor
   4. Rectifier

The advantage of AC over DC is that _____.

1. 1. it contains more electrically energy
   2. it is free from voltage fluctuations
   3. its generation costs much less
   4. it can be transmitted over long distances with minimum power loss

Sun and the othe rstars are virtually huge nuclear explosion chambers producing a large amount of heat and light. Yet, we do not hear any of the explosions because _____.

1. 1. beat and light are electromagnetic radiations and travel much faster than sound.
   2. sound waves get attenuated completely before they reach the earth.
   3. the process involved in the interior of the sun and the stars relate to atomic and subatomic particles and not molecules an their vibrations.
   4. the outer space is an absolute vacuum.

Air bubble in water shines because of the phenomenon of _____.

1. 1. Dispersion
   2. Refraction
   3. Diffraction
   4. Total internal reflection

What are primary colors?

1. 1. Color of the rainbow
   2. Color in the spectrum of white light
   3. Colors which cannot be produced
   4. Color found in nature