A Question of Relative Motion

A very interesting discussion came up the other day while we were having a cup of tea in the canteen. The question in contention was:

If a traveller from India boarded a flight to US and then came back, would it take longer one way than the other?

Assumptions

Several simplifying assumptions were taken: no atmosphere which means no drag, no viscous force etc. etc. And of course, we are to do the correction for the time difference to arrive at the final figure.

Several arguments in favour and against it were put forth. To start off with, A argued that it is a simple case of relative motion. You go one way, your relative velocity is higher. You go the other, your relative velocity is lower. So, obviously, it would take different times. Simple enough.

Bump, an apple hit me! (That makes me Newton v2.0?)

“Do you mean to say that if I were to simply take a plane up in the air and hold it stationary there, I would reach USA after 12 hours?” B put forth. “Or if I throw an apple up in the air in a moving bus, it will come back and hit me”, said B consolidating his argument with an analogy.

Playing with Apples on a Bus Top (Nike?)

C pitched in A’s defence stating that the time period in consideration here was very less. What if I stood on top of the bus and threw an apple up in the air? The bus isn’t accelerating. Would the apple come back on me or would it fall behind?

“Of course, it would come back and drop on me”, said A. “Newton’s first law. A body continues to remain in its state of motion unless acted upon by an external force. The external force while throwing up is only in the vertical direction. So, it continues to move with the velocity of the bus while in air.”

My First love: To be a Space Scientist (Ending up in IIT was chance)

A continues , “How do you think a geo-stationary satellite works? It continues moving and remains above a specific country all the time even though the earth is rotating.” A had now switched sides.

Intimidated and discombobulated, C argued, “OK, but think of this. The plane works on the principle of jet propulsion. There is a horizontal force in action”. Silent upto now, D jumps on board the discussion. “That is not an external force. It works on the principle of conservation of momentum.”

Ricocheting Arguments!!

C put forth a last ditch effort to save his argument. “Fine, but how do you explain this? You board a plane at day time in India and after travelling 15 hours, it is still daytime when you land. That clearly means that your relative position with respect to the sun hasn’t changed much even after 15 hours of flight. Which was what B was saying. I take the plane up. Let it remain stationary with respect to the sun and lo behold! I reach USA. The plane expends all the energy only to remain stationary in space.”

Clearly, everybody was quiet frustrated and disoriented by now. All tea cups were empty. I for a fact decided that this wasn’t my cup of tea. Back in the room, I sat back, relaxed and started my first assignment from CAOS class: Fahrenheit 451.

Post Scripts

PS1: The flow of arguments may not be exactly the same as discussed. Some changes have been made to present all view points. In fact, there were more than four people.

PS2: I checked the flight timings. There seems to be a difference of 3 hours either way in most flights. Don’t ask me why that is.

PS3: If you didn’t read what was written above and directly skipped to the happy ending, to make a long story short: it is a question of relative motion.

Beggars to Entrepreneurs

Travelling in local trains is always a difficult experience. Sometimes it is enlightening too.

This weekend, for example I found that beggars can be entrepreneurs too. They aren’t as dumb as they are made out to be.

Here are some striking instances where the begging party applies itself to the situation at hand.

1. At the ticket counter: If you have ever told a beggar that you don’t have change to give him, beware. Enter the modern day street smart beggar. Standing at the ticket counter, waiting for you to give him the Re 1 change that you got from the counter. No excuses now.
2. Catch me game: This was a really smart lady who sent her small kid to go around to get something. On receiving the coin, the kid would throw the coin or roll it across to her mother as if it were a game he was playing. Not surprisingly, he was more successful than her mother at raising funds. The true virtuosity of the kid came to light when he got a packet of biscuits from a generous bystander and returned beaming to his mother holding it like a trophy.

A third instance, to whom I had referred in passing here, was the snake charming beggar.

Obviously, as impressed I was, so was I distressed. Why did these people not spend their energy on something more productive? Rather than spend their time begging (which did not come across as an easy profession to me), why not go out there and do something of value. Maybe sell some newspapers. Or start a roadside food stall. Or become a local tourist guide. Thousands of possibilities.

What drove them to beg is a mystery to me? Was it their attitude, the government or just chance. I have many questions but no answers.

The Search Ends

After some amount of procrastination, I finally decided to put some of my random thoughts into a structured blog post.

It has been a hectic semester searching for and finalizing internships. After quiet a bit of fight, I will have to settle with Finland. Casting away thoughts of posting a laconic A?! on Facebook as my status message, I think it would be more satisfying going through the whole process step by step and looking at some of the ups and downs I had.

August-September ’10

Internship season begins. After the initial jitters, ITC finally comes to campus. I get my first experience of a real GD. Not to be remembered, I must admit. I had hardly learnt from experiences last year.

September-November ’10

I never thought getting internships could be this hard. ITC selected 8 from the whole batch. Deutsche Bank selected one from the 3rd years. Schlumberger was my best bet. Made it to the interview stage after a somewhat arbitrary GD (Topic was “Rolling & Stones”).

Interview was even more arbit. Here is a sample:

I: Do you drink?

Me: (Brief Pause) No.

I: Do you listen to rock music?

Me: Yes.

I: Which is your favourite band?

Me: Pink Floyd.

I: You don’t drink and listen to Pink Floyd?! Don’t fib! (Laughs)

Me: (Sheepish smile & an awkward silence)

Although everybody described their interviews as good. I knew the moment the interview ended that I had a very slim chance of making it through.

December-January ’10

Companies coming to the campus had started to dry up. Even those that came didn’t sound very attractive. I started to forget about the internship and concentrate on other things.

SF came and went. I made it to the final 6 teams on 2 occasions in a marked improvement over last year’s performance. Some of the keywords that stood out were Suppandi, The Tipping Point and Scrabble!! (That is an in-joke!)

February-March ’10

Finally, internship gets finalized in Finland. I was pretty excited but institute rules and regulations regarding foreign internships somewhat dampened the atmosphere. Couldn’t really define the exact moment when I got the internship. But, I guess I’m pretty satisfied about it. And more than anything else, the work there sounds quiet interesting.

Had my first taste of an inter-hall event in March when I got a bronze in Whats the Good Word. Keywords were Poltu and Farziaap. More about it in the next post. Cheers!!

PS: On a somewhat unrelated note, I love Asok, the intern