Question

At what time between 8-9 will the first right angle will be made by \(\cancel{second}\) minutehand and the hour hand .

Answer 1

Do you have any ideas?

Answer 2

Would it be 9 oclock

Answer 3

Hint:
For every 360 degrees the minutes hand moves, the hours hand moves by 30 degrees, so the two hands approaches or diverges by (360-30)/60 = 11/2 degrees per minute.

Answer 4

connfused

Answer 5

This is the first right angle between the hands between 8 and 9, right?

Answer 6

yes

Answer 7

If the hour hand does not move, we would have a 90 degree at 8:25,agree?

Answer 8

yes

Answer 9

Since the hours hand moves at the rate of 1/12 of the minutes hand, it will take the minutes hand 12/11 of the time (25 minutes) to catch up to the same position of 90 degrees, giving the exact time as 25*12/11=300/11=27 3/11 minutes.

Answer 10

yes its correct thnx

Answer 11

first right angle will be made by `second hand` and the hour hand .

is that a typo ? shouldnt it be `minute hand` ?

Answer 12

yes lol right

Answer 13

Right! An oversight! :) Thank you! @ganeshie8

Answer 14

@jhonyy9