Why do overhead power lines hang lower on hot days?
A) Metal wires expand as temperature rises B) Trapped air slows heat loss from the body C) Evaporation removes heat […]
Every Day Science, Scientific Reasons
Scientific Reasons
Every Day Science, Scientific Reasons
Why do parallel household lights work when one bulb burns out?
A) Light travels much faster than sound in air B) The Doppler effect raises the observed frequency C) It responds […]
Every Day Science, Scientific Reasons
Why do people breathe more rapidly after hard exercise?
A) Excess water is excreted to maintain balance B) Platelets and clotting proteins make a seal C) Working muscles need […]
Every Day Science, Scientific Reasons
Why do railway tracks have small gaps or expansion joints?
A) To make electricity flow B) To increase friction C) To remove gravity D) To allow thermal expansion Answer: D […]
Every Day Science, Scientific Reasons
Why do roots have many root hairs?
A) The heart pumps more blood to active muscles B) Its evaporation removes thermal energy C) They increase surface contact […]
Every Day Science, Scientific Reasons
Why do rubber coverings help make electrical cables safer to touch?
A) Rubber resists the flow of charge B) A longer air column has a lower fundamental frequency C) Separated panes […]
Every Day Science, Scientific Reasons
Why do sealed canned foods last longer than exposed foods?
A) Gas bubbles are less dense than surrounding water B) Fresh solvent contacts the solid more often C) Water and […]
Every Day Science, Scientific Reasons
Why do some seeds fail to sprout in waterlogged soil?
A) Nerve signals stimulate salivary glands B) They may lack oxygen for respiration C) Blinking spreads tears over the eye […]
Every Day Science, Scientific Reasons
Why do stars appear to twinkle more than planets to the unaided eye?
A) Atmospheric turbulence affects their nearly point-like light B) Stars turn on and off C) Planets produce their own stable […]
Every Day Science, Scientific Reasons
Why do stars seem to twinkle more than planets usually do?
A) The image reverses front-to-back relative to the mirror B) Fewer light rays reach the edge from different directions C) […]