Cork-a-Doodle-Do

Rallying around that tumbler, they filled it half full of water first and immediately proceeded to float a cork in the middle.

E4
I must confess that recently I got the distinct impression that my friend Dipankar, who is a nuclear physicist, was goofing off. I mean, instead of mucking around with Higgs particles and other vector bosons that go quark at night, as one would imagine physicists should be deeply delving into, he and some of his colleagues got far more involved in an afternoon with a glass of water and a cork.
Rallying around that tumbler, they filled it half full of water first and immediately proceeded to float a cork in the middle. They found that it would invariably migrate to any one edge of the glass, stick to the wall side, and stay there. On the other hand, when they filled the water right up to the brim and then some and floated that same cork back on, no migration took place. It just hung around there, plumb dead in the middle. In fact, if the cork was deliberately placed towards one edge, it hurried back to the centre.
Now I'm no great physics dude but I still considered things like surface tension, convex and concave meniscuses, Brownian motion, hydrostatic forces and a host of other beauties of fluid dynamics and still came up zilch. But guess what - here's the real snorter: when I asked my friend to spill it, he said he had no idea why but he and his colleagues were working on it. So does anyone want to out physics a physicist?

DEAR MS

(Nobody got the answer to the problem where a monster's prowling around the perimeter of a circular pond while you're in the middle. The monster can move at four times the speed at which you can swim, but if you can reach the shore before it can, you can escape. So how do you do it? - MS)

Beast-Of-Burden Dept:

Solution: Swim straight towards the shore along a radial path up to a distance of 1/4^th times the pond's radius. Then swim along the circumference of an imaginary circle concentric with the pond until you're exactly opposite the monster. You can achieve this since you have a higher angular velocity. Once opposite the monster, swim for the nearest point on the shore. You will get there first because you have to travel less than 1/4^th of the distance that the monster has to travel. - MS
(The other problem was: "What's the smallest number which has to be added to 69241811 to make it a palindrome?" - MS)

More-to-come Dept:

It's 2485. Reason: the closest palindrome to 69241811 would be 69244296; and since we need the smallest addition, we can keep the first four digits the same and then form the next palindrome by reversing the first four digits to get the last four.

• Asma Mustufa, asmamr52@gmail.com

(Among the first five who jumped on to the 2485 bandwagon are: Joel John, joeljo2104@gmail.com; Abhishek Narayan, dudeabhi4u@gmail.com; Jagannathan Narayanan, jnarayanan16@gmail.com; Deepa Shivraj, deepashivraj@gmail.com; Surya Narayanan Krishna Moorthy, surya661666@yahoo.com. However, read on.)
The answer is -58130700. When we add this number, we get 11111111, which qualifies as a palindrome. The trick is "the smallest number" part!

• Ravichandran A V, avrcgc@yahoo.com

As it is not mentioned that it has to be the smallest "positive" number, the answer is -69241800, which, when added to the given number, makes it 11, a palindrome.

• Sheikh Sintha Mathar,

sheikhsm7@gmail.com

ENDGAME(S)

1. The original problem was: "What's the smallest number which has to be added to 69241811 to make it a palindrome?" So what if the answer is actually 4. How is that possible?
2. The letters forming COLD can each be shifted forward three positions in the alphabet to form FROG. Similarly, BALK can be turned into ONYX by shifting them 13 positions ahead. How rapidly can you work backwards from the following 10 words to determine what words we started with: (1) BEEFS; (2) INGOT; (3) LORRY; (4) SORRY; (5) FREUD; (6) FERNS; (7) JOLLY; (8) TOFFS; (9) TIFFS; (10) TIGER.

(To get in touch with Mukul, mail him at mukul.mindsport@gmail.com)

• Mindsport