Physics Chapter 15- Lenses by https://padlet.com/ronaldoyee_161/a4eax7mma8u0 en-us 2016-11-21 00:43:15 UTC 2026-01-23 19:50:52 UTC hello@padlet.com Recall! Reflection and Refraction ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138978193 When light ray travels from water to air,]]> 2016-11-21 00:45:44 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138978193 Parallel light rays reaching a lens ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138978709 The point where light rays meet is known as the focal point. 
This lense, thicker in the middle is called a converging lense. Lenses that are thinner in the middle are called diverging lenses]]> 2016-11-21 00:52:17 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138978709 Focal point and focal length ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138979987 The focal point is the point where light rays coming from far meet.
The focal length is the distance from the centre of the lense to the focal point]]> 2016-11-21 01:08:30 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138979987 Ray diagram ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138980050 A ray diagram is constructed to find out
  • the height of an image
  • whether the image is upright or inverted
  • whether the image is diminished or enlarged
  • where is the image positioned
  • whether or not the image is real or virtual
To draw a ray diagram, draw 2 rays. One passing through the centre of the lens and one parallel to the axis, then passing through the focal point, F.
]]> 2016-11-21 01:09:21 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138980050 Example 1 ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138981555 The lense is the centre vertical line. The axis is the centre horizontal line. The image is real, diminished, inverted and opposite side to the object (meaning it is not at the same side as the lense) ]]> 2016-11-21 01:25:26 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138981555 Example 2 ronaldoyee_161 https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138982424 If the 2 rays do not intersect, draw dotted lines backwards and it will intersect. This situation is known as a virtual image, since the light rays did not reach the image. The image is upright, enlarged and on the same side to the object (meaning it is at the same side as the lense)]]> 2016-11-21 01:35:09 UTC https://padlet.com/ronaldoyee_161/a4eax7mma8u0/wish/138982424