prove that there is no time when the three hands are equally spaced around the clock
ie the hands are equally \[2\pi/3\] away from each other
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hands,A short thick "hour" hand; A long, thinner "minute" hand; A very thin "sweep" seconds hand
revolutions made by each hand hour rev:day 1:12 hours minute 1:1hour sweep 1:1 min=1/60hours
let h ,m,s be the angles produced after time t,where t is in hours
i think we can visualise this as a race to cover a straight line of \[2\pi m\]of length
and the speeds of all of them will be 1/12 rev per hour,1 rev per hour,60 rev per hour
at a certain time t they are equally away from each other
so lets say hour hand has already went y meters so since the sweep hand is the largest then the distance covered by each is s: y+2x=60 rph*t m: y+x=1 rph*t h: y=1/12 rph*t
provided they are x meters away from each other
\[2\pi-(2x+y)=x \implies 2\pi=3x+y\\ y=2\pi-3x\]
so we have to show that there is no such a tym
\[3y+3x=(60+1+\frac{1}{12})t\\6\pi-9x+3x=6\pi-6x=(\frac{733}{12} )t\] \[t=72\frac{\pi-x}{733} \]
so at @Hero wat time is this...where they are all equal
equally diplaced from each other
one unknown, with two equations, you cant have a solution all the time.
getting delayed for dinner, brb... ive used angular velocity equations in the wolfram solution above...
okay guys let me put the original question
in the original question it says this should be obvius and easy to prove ...this was not the question at hand,i jus wanted to show this easy implicit suppossion
i wanted to prove it
why is @Hero laughin...lol
proof is obvious to see cuz x = 3 2x = 3 equations will not have a solution
i was concerned wit this part it is well known,and not difficult to prove, that there is no time when the three hands are equally spaced around the clock, with each separating angle 2π/3.
did u have a look at wolfram link
let me check it ...
t = time in seconds, 1) angle between seconds, minutes = 2pi/3 :- t(2pi/60 - 2pi/(60*60)) =2*pi/3 ---------(1) 2) angle between minutes, hours = 2pi/3 :- t(2pi/(60*60) - 2pi/(60*60*60)) = 2*pi/3 -------(2)
same equation and 60 times of it
there is no solution for above system
okay so thats like the ratio we set up.....okay so we assume there is no solution...for this set,hence no such time exist
wat
when we say there is no solution for below :- x = 3 2x = 3 are we assuming anything ?
3! or 360! ways to make the pattern?
i need to go, cya
okay,c u later
so now we will consider the original question i will ask in a new slide
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