Hanging Out There

Which two would then be sitting together, and who else would be on the same side?

E4
Millions of years ago, when I was seven or eight years old, there was a park in the cantonment where my parents were parked that had a reverse seesaw. Now I can visualise you wondering what the heck that could be. Well, it was a seesaw you couldn't sit on because it was so high up in the air. So, what's the point, I hear you think. You had to HANG from both ends and then go up and down. Cool or what? The following problem could apply to it too.
J decides to use a seesaw to demonstrate the principles of balance, and of moments, to his family. A, B, C, D, E and F weigh 100, 80, 70, 60, 50 and 20 kilos, respectively. The seesaw has three seats on each side, positioned one, two and three metres from the centre. They discover many ways of balancing, using some or all of the family. In one particular combination, with at most one person on each seat, one of the family members not on the seesaw observes that the sum of the moments of all the people on the seesaw is a square. "That's right," says J. "But as you can see, it doesn't balance - and, what's more, there's nowhere you can sit to make it balance," says the relative. "Wrong. I could sit on someone's lap," J says. "True, but only if you sit at the end," replies the family member. Which two would then be sitting together, and who else would be on the same side?
DEAR MS
(The older leftover problem was: "Why are the rear wheels of some three-wheeler vehicles inclined inwards? Wouldn't an outward inclination give it more stability?" - MS)
Behind-The-Wheel Dept:
A vehicle that has one wheel in front and two in the rear reduces the cost of power in the steering mechanism, but it greatly decreases the lateral stability when cornering, while the brakes are applied. The real problem of a three-wheel configuration is lateral instability (which means, when the rear wheels are inclined outwards), the car therefore tips over in a turn, before it starts to slide. However, it can prevented.
Amatul Nadia, ?amatul.nadia@gmail.com 
(On the other hand, the double-barrelled later problem was: 1. "What is the only word in the English dictionary that has a silent 'z'?" and 2. "What is the shortest word in the English language to contain all of the vowels?" - MS)
Zero-Zs Dept:
For the first endgame: There are more than one or two words in the English language that contain a silent 'z'. They are RENDEZVOUS, CHEZ (preposition) and LAISSEZ FAIRE (an adjective). As for the second endgame: The smallest word in the English language to contain all the vowels is IOUEA (genus of some fossil sponges). This word is officially certified by the Wikipedia dictionary.
akshit0201@gmail.com
(1). The word in English dictionary that has a silent 'z' is RENDEZVOUS, which was not too difficult to fathom; since it is a common one. (2) EUNOIA is the shortest English word containing all the five vowels. It comes from Greek and means 'well mind' or 'beautiful thinking'.
Saifuddin S F Khomosi, ?saif_sfk@hotmail.com 
(In the meantime here's a further thought. - MS)
Castled-Again Dept:
The answer of the first chess problem as 18 moves of the rook (with paths overwritten) is wrong. The correct answer is 16 moves (with paths overwritten). Even my answer sent earlier as 17 moves was wrong.
Abhay Prakash, ?abhayprakash@hotmail.com 
ENDGAME(S)
1. You've seen lighters that use friction against a flint to produce a spark and also those that use a battery. But how do the ones which use neither of these things - such as the gas lighter used in kitchens to light the burners - work?
2. Why are the nostrils of a dead body plugged with cotton? Why not the ears and mouth too? 
(To get in touch with Mukul, mail him at mukul.mindsport@gmail.com)

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