Why does a pencil look broken if you hold it at an angle in a beaker of water?
It is ok
When a pencil is immersed in water in a beaker, the phenomenon you observe where the pencil appears broken is known as refraction. Refraction occurs because light waves change direction when they pass through different mediums, such as air and water.
When light travels from air (a less dense medium) to water (a denser medium), it slows down and bends towards the normal, an imaginary line perpendicular to the surface of the water. Conversely, when light travels from water to air, it speeds up and bends away from the normal.
So, when you hold a pencil at an angle inside the water, the light rays coming from the pencil to your eyes undergo refraction at the air-water interface. This causes the light rays to change direction, making the light appear to come from a different position than where the pencil actually is. As a result, the pencil appears broken at the water's surface, creating an optical illusion.
When a pencil is held at an angle in a beaker of water, it appears broken due to a phenomenon called refraction. Refraction is the bending of light as it passes from one medium (such as air) to another (such as water) with a different density.
To understand why the pencil looks broken, we need to consider how light travels through different mediums. When light travels through air, it moves in a straight line. However, when it encounters water, which has a different density, its speed and direction change. This change in speed and direction causes the light rays to bend.
When you place the pencil in the water, the light rays from the submerged portion of the pencil enter the water and bend towards the normal (an imaginary line perpendicular to the water's surface). Similarly, when the light rays exit the water and re-enter the air, they bend away from the normal. This bending of light is what causes the pencil to appear broken.
To visualize this effect, you can conduct a simple experiment. Fill a transparent container, like a beaker, with water. Place a pencil partially in the water and observe how it appears to be broken at the water's surface. You can also try different angles and depths to see how the apparent "break" changes.
In conclusion, when a pencil is held at an angle in a beaker of water, it appears broken due to the bending of light rays as they pass from one medium (air) to another (water), which is known as refraction.
It's a property of light called refraction. When light enters the water, it can't move as fast and it has to slow down slightly. It's kind of like how if you are walking, you can walk at a normal speed but if you walk in water, you can't walk quite as fast.
If light from the image enters the water straight, then the image looks normal - which was what you originally did when the pencil was straight up and down. If the light enters the water at an angle, then the change in speed between the open air and water causes the light beam to bend away from its original path. When the pencil was at an angle, the image was at a bigger angle in the water than in the air and made the pencil look like it was bent.