Aptitude - Clock - Discussion
Discussion Forum : Clock - General Questions (Q.No. 11)
11.
How many times are the hands of a clock at right angle in a day?
Answer: Option
Explanation:
In 12 hours, they are at right angles 22 times.
In 24 hours, they are at right angles 44 times.
Discussion:
80 comments Page 2 of 8.
Raju said:
1 decade ago
Actually in general for every hour the right angle comes in two times.
So, the answer should be 2*12*2 = 48 times.
But the logical thing here is for 2 o clock and 3 o'clock, one right angle coincides,
Similarly for 8 and 9 o'clock another right angle coincides.
So, the final answer is 48-2 = 44
So, the answer should be 2*12*2 = 48 times.
But the logical thing here is for 2 o clock and 3 o'clock, one right angle coincides,
Similarly for 8 and 9 o'clock another right angle coincides.
So, the final answer is 48-2 = 44
Shuham singh said:
9 years ago
Suppose you are starting counting number of right angles from midnight 12:00 clock.
Then in first 12 hours.
All hour makes a right angle 2 times except starting 12:00 clock and ending 11:00 clock only-only 1 time.
That's why in 12 hours it is 22 times. And in 24 hours it is 44 times.
Then in first 12 hours.
All hour makes a right angle 2 times except starting 12:00 clock and ending 11:00 clock only-only 1 time.
That's why in 12 hours it is 22 times. And in 24 hours it is 44 times.
Prashant kumar said:
1 decade ago
In 60 min. 55 mins are gained by minute hand i.e. in 1 hour, hour hand lags by 5 mins.
in 12 hrs. , hour hand lags by 12*5=60 mins. i.e. 1 hr.
and in 1 hr dere r 2 right angles
hence in 12 hrs. 2 right angles will be lost resulting 22 instead of 22 and hence 44 in 24 hrs.
in 12 hrs. , hour hand lags by 12*5=60 mins. i.e. 1 hr.
and in 1 hr dere r 2 right angles
hence in 12 hrs. 2 right angles will be lost resulting 22 instead of 22 and hence 44 in 24 hrs.
Pratik said:
7 years ago
Every hour, 2 right angles are formed between the hands. But because minute hand crosses hour hand every 55 mins, every hour, there is a 5-minute lag. For 24 hours, the lag is 24x5= 120 mins i.e. 2 hour lag - a loss of 4 right angles in 24 hours.
So: 24x2 - loss = 44.
So: 24x2 - loss = 44.
(5)
Bharathveer reddy said:
1 decade ago
Generally for every 1 hr at two points it makes right angles.
But between 2:00 to 4:00 we get 3 right angles (approx 2:25, 3:00, 3:30) instead of 4 times.
Similarly between 8 and 10.
So we get 22 for 12 hrs and 44 for 24 hrs.
But between 2:00 to 4:00 we get 3 right angles (approx 2:25, 3:00, 3:30) instead of 4 times.
Similarly between 8 and 10.
So we get 22 for 12 hrs and 44 for 24 hrs.
Sonu Choudhary said:
1 decade ago
If you switch to a rotating coordinate system in which the hour hand stands still, then the minute hand makes only 11 revolutions, and so it is at right angles with the hour hand 22 times.
In a 24 hour day you get 2*22 = 44.
In a 24 hour day you get 2*22 = 44.
Prashant bhalani said:
1 decade ago
We know very well that both hands meet 11 times in 12 hours and therefor 22 times in 24 hours.
Considering process of meeting,
Both hands will be at right angle for 2 times per meeting.
So 22*2 = 44 times..!!
Simple as that.
Considering process of meeting,
Both hands will be at right angle for 2 times per meeting.
So 22*2 = 44 times..!!
Simple as that.
(1)
Shawisk said:
1 decade ago
Yes right angel in 12 hours is 22 times.
Approximate time is.
00:15.
00:49.
01:20.
01:55.
02:25.
03:00.
03:30.
04:05.
04:40.
05:10.
05:45.
06:15.
06:50.
07:20.
07:55.
08:25.
09:00.
09:30.
10:05.
10:35.
11:10.
11:40.
Approximate time is.
00:15.
00:49.
01:20.
01:55.
02:25.
03:00.
03:30.
04:05.
04:40.
05:10.
05:45.
06:15.
06:50.
07:20.
07:55.
08:25.
09:00.
09:30.
10:05.
10:35.
11:10.
11:40.
(2)
Mansi said:
7 years ago
A unique clock has 24 divisions instead of 12 nd functions like normal then how many times from noon will the hour and the minute hand form 90 degrees for the first time? Can anyone answer this?
(3)
Himanshu said:
10 years ago
@Shawisk. The question is absurd. Because even at 1:20, the hr hand will be slightly ahead of 1 while minute hand will be at 4. Therefore making an angle of less than 15. Kindly help.
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