light & shadows

light travels in a straight line

mirrors

transparent: allows most light to pass through

translucent: allows some light to pass through

opaque: do not allow light to pass through

shadow can ONLY be formed by translucent or opaque object

heat & temperature

heat V temperature

heat: form of energy

temperature: measurement of degree of hotness

heat flows from hotter → cooler

heat termperature object
gain increase expand
lose decrease contract

precautions against expansion and contraction:

winter → temp decrease → heat loss → contract

gain heat → expand

good(metals) & poor conductors of heat