Why do firemen crawl in smoke filled rooms? plus 9 more videos.. #aumsum #kids #science

Density - Why do firemen crawl in smoke filled rooms? Sublimation - Why do mothballs disappear over time? Ultrasound - Why is ultrasound used in sonar? Refraction of Light - Why does a pencil look bent in water? Stomata - Why do water lilies have stomata on the upper side of their leaves? Frequency - Why do women have shriller voices than men? Diffusion - Why can we smell hot food from a distance? Density - Why does an iron nail float on mercury and sink in water? Earthing - Why do buildings have lightning rods? Rust - Why is oxalic acid used to remove rust stains?