1. Illuminance of a surface is proportional to the power of the light source and inversely proportional to the square of the _______.   distance   area   luminous intensity   Hint Half-n-half Clue   2. If the power of a light source is measured in candelas and distance in meters, then the illuminance of the surface is in   Joule   Lux   Watt   Half-n-half Clue   3. Light always travels in straight lines.   True   False   4. A lunar eclipse occurs when the earth comes between the sun and the moon.   True   False   5. Bodies that radiate light are called   luminous   non-luminous   opaque   Half-n-half Clue   6. Materials through which light cannot pass are said to be   translucent   transparent   opaque   Half-n-half Clue   7. A _______ eclipse occurs when the moon comes between the sun and the earth.   lunar   solar