If someone presses a pointed needle against your skin, your are hurt. But if someone presses as rod against your skin with the same force you easily tolerate. Explain

Do you feel any sensation on your skin?

Rub your palms against each other and put them on your cheeks. What do you feel?

Write a short letter to someone you know about your having learnt to do something new.

A coin is placed at the bottom of a tin can. Move your eyes until the coin is just out of sight (see diagram). Keep your eyes in this position while someone pours water gradually into the tin can. What would you observe ? Explain your observation.