Refraction

• Refraction is when waves bend when entering a new substance. It changes direction because it speeds up or slows down
• WAVES SLOW DOWN WHEN ENTERING DENSER SUBSTANCES

  • E.g. when air travels from air(less dense) into glass(more dense) It slows down and cause ray to bend towards the normal
• WAVES SPEED UP WHEN THEY ENTER LESS DENSE SUBSTANCES

  • E.g. when wave travels from glass(more dense) into air (less dense). This cause ray to bend away from normal
• The greater the difference between densities, the more the refracted light bends.
• When light enters water from air, it bends towards the normal as it slows down. When light leaves water and goes back into air, it bends away from the normal as it speeds up again.