Why is the sky clear in the day and dark at night?
Experiment: Day and night
Hypotheses: Ask children to explain what causes day and night. What brings us the light of day? Where does the sun go during the night?
- A globe
- A table lamp without a lamp-shade or a flashlight
- A sticker which can be used to identify the country you live in on the globe
- This experiment is a demonstration done by your caregiver.
- With your friends and caregiver, observe the globe and try to identify the country you live in. Put a sticker on it. Can you name other countries? Try to identify as many as possible.
- Make the room as dark as possible. Turn the lights off and close the curtains. The only light present must be the light of the table lamp or flashlight. This light must be fixed. It mustn't be moved throughout the experiment.
- Your caregiver places the globe approximately one meter from the light source, with your country facing the light. Do you think this represents the day or night?
- Next, your caregiver turns the globe 180⁰ on its axis (without moving it transversally) so that the identified location is plunged into darkness. It is night-time.
- Continue to turn the globe, always in the same direction, to observe a few cycles of night and day. In real life, how long do you think it takes the Earth to complete a full turn?
Explanation: I am sure you have already heard someone say that the sun rises in the morning and sets in the evening. Often, it seems as if the sun moves across the sky but this is just an illusion. The sun does not move! In fact, it is the Earth which turns on its axis nonstop. The sun always shines. When it is night-time where we live, it is daytime in faraway countries located on the other side of the Earth (in China or Australia for example). It takes the Earth approximately 24 hours to complete a full rotation. This explains why our days last 24 hours!
has a Bachelor's Degree in Biological Science. She has worked in a laboratory and tested her knowledge. She has taught Math, Chemistry, and Physics. She has also developed a simplistic and innovative approach designed to introduce young children to scientific experiments, old and new. She created her friend Globule. This character is sometimes red, and sometimes white. He guides little ones through their scientific experiments and discoveries. It is clear to see Angélique is passionate about children and science. Globule's Approach.