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Newton’s Trinity College Notebook is Online!
Cambridge Digital Library had made Newton’s exceptionally great works online.
Some times ago they added the Trinity College Notebook by Isaac Newton, which he used to teach in the college in 17th century.
Read More About the Project Here.
List of other works of Newton can be found at www.newton.ac.uk/newton.html.
Three Children, Two Friends and One Mathematical Puzzle
Robert Said: I am now married and have three children.
Thomas Said: That’s great! How old they are?
Robert: Thomas! Guess it yourself with some clues provided by me. The product of the ages of my children is 36.
Thomas: Hmm… Not so helpful clue. Can you please give one more?
Robert: Yeah! Can you see the number on the house across the street?
Thomas: Yes! I can.
Robert: The sum of their ages equal that number.
Thomas: Sorry! I still could not determine their ages.
Robert: My oldest child has red hair.
Thomas: OH.. Oldest one? Finally I got it. I know age of each of your children.
Question:
What were the ages of Robert’s children and how did Thomas know?
Discussion and probable answer
This is a very good logical problem. To do it, first write down all the real possibilities that the number on that building might have been. Assuming integer ages one get get the following which equal 36 when multiplied:
| Age of 1st | Age of 2nd | Age of 3rd | Sum(HouseNo.) |
| 1 | 1 | 36 | 38 |
| 1 | 2 | 18 | 21 |
| 1 | 3 | 12 | 16 |
| 1 | 4 | 9 | 14 |
| 1 | 6 | 6 | 13 |
| 2 | 2 | 9 | 13 |
| 2 | 3 | 6 | 11 |
| 3 | 3 | 4 | 10 |
The biggest clue is that the Thomas DID NOT KNOW after having been told the sum equaled the number on the house. Why didn’t he know? The only reason would be that the number was 13, in which case there are two possible answers. For any other number, the answer is unique and the Thomas would have known after the second clue. So he asked for a third clue. The clue that the oldest had red hair is really just saying that there is an “oldest”, meaning that the older two are not twins. Hence, the answer is that the redhead is 9 years old, and the younger two are both 2 years old.
Source of The Puzzle: This puzzle is a modified form of a puzzle from Science Reporter Magazine, Hindi 1996 and I have changed the names from Ram and Shyam to Robert and Thomas to make this puzzle convenient to read.
Related articles
- Just another way to Multiply (wpgaurav.wordpress.com)
Nanostory of Nanotechnology
Fullerene
Well, this is not going to be a nano [very short] story either of fairies or aliens. This is a big story of Nanotechnology, one of the most advanced topics in physics. Wait. It’s not going to be so hard or advanced to read. It is really going to be a good story because I’m not going to teach you about this stuff. I am trying to say and save it’s history on MY DIGITAL NOTEBOOK. I think you all should also read this.
Nanotechnology has become a widely discussed topic today in newspapers, magazines, journals, blogs and even in television ads. It’s very common that some organization announcing ‘yet another’ “nano-conference”. Nanotechnology or nano tech in short, refers to the technology of creating materials, devices and functions using atomically manipulated matter. If you didn’t understand it clearly yet read further lines. (more…)
The Fear, and the Use, of Mathematics and Physics
Image via Wikipedia
The two areas of human enquiry that inspire the greatest terror in the hearts of students are undoubtedly mathematics and physics. You may find history or chemistry or economics difficult, but your reaction to these subjects, and more others is almost certainly not fear. On the other hand, when you encounter an equation, your first reaction is to escape to more amiable company. If you compare subjects to people, you will realize that your reaction to maths or physics is very similar to your reaction to a stern, quiet person who is famous for his wisdom but who makes you very uncomfortable indeed. When he speaks you listen dutifully, because you’ve been told his words contain a lot of meaning, but you understand almost nothing, and you end up feeling foolish and exposed; and what is worse, this person does not need to shout to make you feel this way — he just has to look at you. When you see an equation or a mathematical expression you react in the same way. Let us try to under stand that what mathematics is and why it is so difficult.
Albert Einstein and His introduction to the Concept of Relativity
Albert Einstein
This name need not be explained. Albert Einstein is considered to be one of the best physicists in the human history.
The twentieth century has undoubtedly been the most significant for the advance of science, in general, and Physics, in particular. And Einstein is the most luminated star of the 20th century. He literally created cm upheaval by the publication, in quick succession, in the year 1905, two epoch-making papers, on the concept of the photon and on the Electrodynamics of moving bodies respectively, with yet another on the Mathematical analysis of Brownian Motion thrown in, in between.
The Electrodynamics of moving bodies was the biggest sensation and it demolished at one stroke some of the most cherished and supposedly infallable laws and concepts and gave the breath takingly new idea of the relativity of space and time.
