Page 6 - Active Science 5 Ebook and Activity

Tell Me Why?

Why do astronauts wear space suits?
There is no air in space to breathe and the temperature is either
too hot or too cold. The spacesuits of the astronauts are especially
designed to carry the oxygen required for them, This is to breathe and
protect them from extreme temperatures.

Why does the wind blow?
Moving air is called wind. The
heat of the sun heats up the
air. Due to this, the warm air gets
lighter and rises up. The cooler
air is heavier and this takes place of the warmer air. This
gentle movement of air is called breeze. When the wind
blows very fast, it creates storm.

Why do thunderstorms occur?
A thunderstorm is a storm in which there is thunder and
lightning and a lot of heavy rain. The air rises up along with
lot of moisture. After rising up to a certain height, water
vapours cool down and start coming down in the form of
water droplets. This swift drifting of water droplets creates
electricity among clouds and causes formation of lighting
and sound. This is called thunderstorm.

Why can’t we see in the dark?
We cannot see when it is dark because the structure of the
human eye is not adapted for darkness. The black hole in
the eye which is called the pupil receives the light. The light
bounces off everything around us and in through this hole
because of which we are able to see. Messages are then
sent from the eyes to the brain telling us what we are looking
at.