Tuesday, October 13, 2015

Terminal velocity

This MCQ can be solved by the method of elimination. 


How do you solve it from first principles?




Monday, October 5, 2015

Terminal Velocity

This question caused quite an avid discussion amongst Physics Educators recently. So I dug out the TYS and found the question and model answer. 




I simulated the same event using a ball and a cylinder half filled with water and took the following video: 

video

Using the video motion analysis, the velocity-time graph below is obtained:



Sunday, October 4, 2015

Reflection and Refraction at the same time!

In most textbooks, Reflection and Refraction are taught as independent topics. However, in this question, it is implied to students that both processes can happen at the same time. 

To the teacher, it is useful to learn about Fresnel Equations that give rise to both processes happening at the glass-air interface.

Here is an experiment that I have done using a laser pointer:



More information can be found here:
http://www.ece.rice.edu/~daniel/262/pdf/lecture13.pdf

Friday, October 2, 2015