______is primary source of light. 

______ is the scientific study of light andhow it interacts with materials.

_______is the bending of light as it passes through different material. 

4._______ It used to measure much longer length;like length of a football pitch. 

______ It is a metal ruler that rolls out and can be carried along, clipped to your belt. 

What heating element found inside the flashlight bulb?

Identify the name of the constellation that consist of five stars that seem to form the letter W.

8.It is a natural force of attractionbetween massive bodies in the universe.

The point of an orbit when planet isclosest to the sun is called_________?

The point of an orbit when planet isFarthest to the sun is called_________?

The flow of warm air rising and cold airsinking. It forms wind or air in motion.

The most important male sex hormone.

 It is a form of asexual reproduction in which an egg develops into an individual without being fertilized.

How long does a day last on moon?

The area where the ocean meets the land,where the shore is pounded by waves during high tide and exposed to sun during low tide.