Question 35
A clock is showing 12:00. After what time will the angle between the minute hand and the hour hand be $$90^o$$?
Solution
Angle = [(11 / 2) M - 30 H]
SInce the hour hand at 12, we put H = 0.
Let's find the value of M. 90 = (11/2)M
M = 180/11 = 16.36
16 min 21sec
Minutes and hours hand will be $$90^o$$ far when the angle between the is $$270^o$$.
270 = (11/2)M
M = 49.09
This is 49 min 5sec
