Why does a ruler appear bent in water

When we look at the portion of the ruler that is outside the glass of water, light from the ruler travels in a straight path to the eye. However, when we look at the ruler within the water, the light is refracted as it passes from the liquid into the air.

Furthermore, the type of liquid impacts refraction. This is because different materials have different indexes of refraction. Objects in water appear larger than objects in the air. The index of refraction for air is 1. The index of refraction for water is 1. This larger index of refraction for water means that the angle the rays of light reach your eyes is larger in water than the angle would be in the air.

This increase in the angle size of light to your eyes makes the object look larger in water than how it looks in the air. The ruler looks larger still in rubbing alcohol and especially in cooking oil because the index of refraction for rubbing alcohol is 1.

Why does the Arrow Change Direction — Watch in amazement as the arrow to changes direction. Can Water Bend a Straw — Another simple and fun experiment that shows refraction in action. Slowly pour rubbing alcohol into the glass until the glass is almost full of liquid. Light also has to work a little harder to get through water. What other light activities can you try with your kids after doing this one? Share your ideas with us!

Put the pencil in the water. Look at it from the top. Look at it from the side. Bending a Pencil Science Explained Light refraction occurs when something gets in the way of the light waves. What you need Clear, round drinking glass Pencil Tap water Make it Fill the drinking glass about two thirds of the way with water.

Test it Bend down until you are looking in line with the top of the water. Explain it Light travels through different materials, or mediums, at different speeds. Observe It Many birds hunt by flying over the surface of water, then diving in once they see a fish. Go further Draw an arrow on a piece of paper and hold it up behind the glass of water, about 30 cm from your eyes. As if by magic, the arrow flips around!

Canada Science and Technology Museum. Program Location.