Different Lens Ray Diagram questions

Drawing ray diagrams for converging lens come in many forms. But the basic concepts needed are the 3 rays (which have rules to follow) to locate the image.

The following ray diagrams for the 4 scenarios must be learned well, together with the respective image characteristics and applications.

With the basic concepts learned, when questions are asked in different ways, you should be able to draw the ray diagrams. Refer to some different ray diagram questions below and their video tutorials.

Example A

Example B

Example C

Example D

Example E

Example F

Example G

Example H

Example I

Example J

During impact of a free falling ball, the force on ground is greater than the weight of ball

In this post, it shows a free-falling ball from a height of 1.0 m. During the impact, the direction of the force on the ground is downwards and the force on the ground by the ball is greater then the weight.

As the ball is free-falling, the only force acting is its weight downwards. Hence a common misconception is to think that the force on the ground during impact is equal to the weight. This is wrong.

The normal force (force on the ball by the ground = stopping force on the ball by the ground) is greater than the weight.

The force on the ball by the ground is equal and opposite to the force on the ground by the ball. Hence the magnitude of the force on the ground is greater than the weight.

Similar concept can be applied if a man jumps off from a height. But in this case, the man’s leg will exert a stopping force over a short distance. That stopping force, once again, is greater than the weight of the man.

Pins inside and outside of beaker filled with water – 2012 sciphy practical

A pin in the beaker of water appears higher than its actual position due to refraction of light.

In this experiment, you have to adjust the pin at the cork to a suitable height, such that the pin and the image of the pin inside the beaker of water is aligned and that ‘pins at position of no parallax’ position.

The video below guides you in adjusting the height of the pins to locate correct height.