I've always wondered about two things concerning magnets: (a) Does a magnet weigh different from its actual weight due to the Earth's magnetic field? And (b) Can one weigh a magnet on metal plated kitchen scales? Regarding (b), read what one person's experience was like below.
I got hold of a set of kitchen weighing scales which are made of some ferromagnetic plate and my neodymium magnets. The reading on the weighing scales increases as you bring the magnet near the weighing plate, as expected. It then reaches a maximum just before you touch the magnets to the plate. The moment you let the magnets hit the scales though, the reading simply goes down to the weight of the magnets (in my case, nearly a fifth of the maximum reading). Can anyone explain this? Or if that's too easy, try (a) instead.
(The leftover problem was: "Bowler bowls, batsman misses, ball misses wicket, keeper can't collect, ball keeps going. Batsmen go for a run, fielder fields ball, throws it to keeper who, before non-striker can make it to crease, whips the bails off. Who's out: striker stumped or non-striker run out? - MS)
The dismissal of the striker or the non-striker depends on who was closer to the crease where the wicket was taken. The one who is closer is declared out. Since, in the question, you are specifying the non-striker is unable to make it to the crease when the wicket is taken, and the striker has already reached his crease (that's on the opposite end from where he started), I guess the non-striker is out.
- Akshit, firstname.lastname@example.org
According to law #39, a batsman cannot be stumped out if he has attempted a run, so the non-striker is run out.
- Hasrat Parkar, email@example.com
(The second one was: "In a 24-hour digital clock with hh:mm format displaying time
from 00:00 till 23:59, how many times in a day will the display be exactly the same as its mirror image? Also, what if it is a 12-hour clock?" - MS)
Totally, five times for a 24-hour clock: 00:00, 02:50, 05:20, 20:05, 22:55. For a 12-hour clock: First three of above, twice during a 24-hour period; if it displays 00:00 at both midday and midnight, it is 3*2 = 6 times. However, as most clocks show 12:00 at noon, it will be only five times.
- Kishore Rao,
(Third: "There are two water tanks of equal capacity with same sized water outlets connected to two taps. One is just above a bucket and the other is 10 metres above a bucket. Both taps are opened at the same time. Which will fill faster?" - MS)
The bucket placed 10 metres below the water tank will fill faster because the flow pressure of the water from the tap of the tank will be greater. Thus, for a good water supply, the tank must always be placed a few metres higher than the level at which supply of the water has to be made.
- Sanskruti Wadhwani, sanskrutiwadhwani96
In the second case, the total pressure head at the pipe outlet is equal to atmospheric pressure plus the height of water in the tank plus 10 metres of static head. The total pressure head being greater, the velocity of water through the tap will also be higher and thus the bucket will be filled faster.
- K Narayana Murty,
1. Can anyone submit an elegantly worked out answer to the following without Googling or using any other aid? What remainder do you get when you divide 100^100 by 11?
2. In a key scene in the film Mackenna's Gold, a lengthening shadow at sunrise points to a particular location. This, of course, is rubbish because as the sun rises, shadows shorten, not lengthen. However, is there any situation when they can lengthen?
(Mukul can be reached at firstname.lastname@example.org)