document.write( "Question 785545: At what time after 8:00 PM
\n" ); document.write( "will the second hand bisect the
\n" ); document.write( "angle formed by the minute
\n" ); document.write( "hand and hour hand?
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #477693 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
The hour hand sweeps through \"360%5Eo\" in 12 hours (\"12%2A60minutes=720minutes\")
\n" ); document.write( "That angular velocity could be stated as
\n" ); document.write( "\"360%5Eo%2F%28%22720+minutes%22%29=0.5%5Eo\"per minute.
\n" ); document.write( "
\n" ); document.write( "The minute hand sweeps through \"360%5Eo\" in 60 minutes
\n" ); document.write( "That angular velocity could be stated as
\n" ); document.write( "\"360%5Eo%2F%28%2260+minutes%22%29=6%5Eo\"per minute.
\n" ); document.write( "
\n" ); document.write( "The second hand sweeps through \"360%5Eo\" in 1 minutes
\n" ); document.write( "That angular velocity could be stated as
\n" ); document.write( "\"360%5Eo\"per minute.
\n" ); document.write( "
\n" ); document.write( "At 8:00:00 PM, the second hand amd the minute hand are pointing up, to 12, while the hour hand points to 8. They are forming 2 angles that add up to \"360%5Eo\":
\n" ); document.write( "One is the \"240%5Eo\" angle containing the numbers from 1 through 7, and the other is the \"120%5Eo\" angle containing the numbers 9, 10, ans 11.
\n" ); document.write( "After 8:00:00 PM, the second hand starts racing towards the hour hand, ahead of the slower minute hand.
\n" ); document.write( "In 20 seconds it is 8:00:20 PM.
\n" ); document.write( "The second hand has swept \"120%5Eo\" and is pointing at 4; the minute hand has swept only \"2%5Eo\", and the hour hand has barely moved half a hair.
\n" ); document.write( "At that point the second hand is almost bisecting the angle (about \"238%5Eo\") formed by the minute
\n" ); document.write( "hand and hour hand.
\n" ); document.write( "If we do not need to be too accurate, we could say that at that time it is bisecting the angle formed by the minute
\n" ); document.write( "hand and hour hand.
\n" ); document.write( "If we need to be more precise, we can calculate angles a s a funtion of time.
\n" ); document.write( "With \"t\"= minutes since 8:00:00 PM, the angles, counted clockwise betweeen the 12 o'clock position and each hand are:
\n" ); document.write( "\"S%28t%29=t%2A360%5Eo\" for the second hand,
\n" ); document.write( "\"M%28t%29=t%2A6%5Eo\" for the minute hand, and
\n" ); document.write( "\"H%28t%29=%288%2F12%29%2A360%5Eo%2Bt%2A0.5%5Eo=240%5Eo%2Bt%2A0.5%5Eo\" for the hour hand.
\n" ); document.write( "To bisect bisecting the angle formed by the minute hand and hour hand, the second hand needs to form an angle of
\n" ); document.write( ".
\n" ); document.write( "(That is the average of \"M%28t%29\" and \"H%28t%29\").
\n" ); document.write( "\"S%28t%29\" will be exactly that angle when
\n" ); document.write( "\"t%2A360%5Eo=120%5Eo%2Bt%2A3.25%5Eo\"-->\"t%2A360%5Eo-t%2A3.25%5Eo=120%5Eo\"-->\"t%2A356.75%5Eo=120%5Eo\"-->\"t=120%2F356.75\".
\n" ); document.write( "That is the time in minutes after 8:00:00PM.
\n" ); document.write( "In seconds, it is \"60%2A120%2F356.75=21.1822\".
\n" ); document.write( "The second hand first bisects the angle formed by the minute hand and hour hand at 8:00:20.18 PM.
\n" ); document.write( "It will happen again at about 8:00:50 PM, and again a little after 8:01:20 PM, and it will keep happening at intervals a hair longer than 30 seconds.
\n" ); document.write( "
\n" );