Physics PDF

Pi can be found almost anywhere.


A colleague recently showed me this amazing video. Were you familiar with this manifestation of Pi in nature?

In case you are interested, 3Blue1Brown uploaded a demonstration of this as a subsequent video on YouTube. How about trying to prove this by yourself?

How many will die?


There are N bottles, from which one contains a lethal poison that would kill whoever drinks from it in exactly 1 week.

What is the minimum number of people you need in order to determine which bottle contains the poison? You have just one week to find out which bottle it is.

A possible solution would be to use N people. Make each person drink from a different bottle and whoever dies after a week will tell us which bottle is poisoned. Can you do better?

Here I wrote a C++ code that will tell you the minimum number of people you need for any given number of bottles. Try to get the correct answer for N bottles and test your answer with the code. As a last resort you can reverse engineer my code to get the answer.

What time is it?


How long does it take for a physicist to tell you what time it is? Try first defining what the concept of time it self means.

Professor Brian Cox and Harry Hill talk about time:

Chess Puzzle


How many pieces can you fit into a chess board?

The rules are:

  • You can only have either knights, bishops, and rooks.
  • The number of knights, bishops, and rooks must be equal.
  • Each piece has to be attacked by one and only one other piece.

I was able to fit 8 of each:


Can you do better?