Clocks
Question 1 |
In a clock, the time is 3.25.What is the angle between the hour hand and the minute hand of the clock:
95/2 degrees | |
90/3 degrees | |
94/3 degrees | |
95/3 degrees |
Discuss it
Question 1 Explanation:
As, the hour hand covers 360 degrees in 12 hrs.
In the clock the time is 3.25 = 3 hrs 25 min = 41/12 hrs.
So, the angle traced by hour hand = (360/12 x 41/12) degrees = 205 degrees.
The minute hand covers 360 degrees in 60 minutes.
So, the angle is traced by minute hand in 25 min = (360/60 x 25) degrees = 150 degrees.
Hence, the required angle of the clock = (150- 205/2) degrees = 95/2 degrees.
Question 2 |
A clock gains uniformly 5 min slow at 8 o’clock in the morning on Sunday and 5 min 48 sec fast at 8 pm on following Sunday. The correct time and day are:
21 min past 7 pm and Wednesday | |
20 min past 7 pm and Thursday | |
21 min past 7 pm and Thursday
| |
20 min past 7 pm and Wednesday
|
Discuss it
Question 2 Explanation:
The given time from 8:00 am on Sunday to 8 pm on following Sunday = 7 days 12 hrs = 180 hrs.
So, the clock gains = (5 + 29/5)min = 54/5 min in 180 hrs.
Hence, 5 min are gained in (180 x 5/54 x 5)hrs = 83 hrs 20 min = 3 days 11 hrs 20 min.
The clock is correct 3 days 11 hrs 20 min after 8 am of Sunday.
So, the correct time and day will be 20 min past 7 pm on Wednesday.
Question 3 |
Sam sets alarm at 5 am. But the clock loses 16 minutes in 24 hours. Effectively, the clock indicates 10:00 pm on the 4th day. Find out the original time of the clock:
9 pm | |
10 pm
| |
11 pm | |
08 pm |
Discuss it
Question 3 Explanation:
From the given information the time from 5 am on a day to 10 pm on the 4th day is 89 hrs.
So, 23 hrs 44 min of this clock = 24 hrs of correct clock.
Hence, 356/15 hrs of this clock = 24 hrs of correct clock.
89 hrs of the clock = (24 x 15/356 x 89)hrs of correct clock = 90 hrs of correct clock.
Hence, the original time will be 11 pm.
Question 4 |
The time of a clock is 8 am. Suddenly the clock gains 10 minutes in 24 hours. Find out the original time if the time of the clock is 1 pm on the following day:
48 minutes past 12 | |
47 minutes past 10
| |
48 minutes past 11
| |
48 minutes past 11
|
Discuss it
Question 4 Explanation:
From 8 am on a day to 1 pm on the following day will be 29 hrs.
So, the clock gains 10 min in 24 hours = 24 hrs of the correct time.
Hence, 145/6 hrs of the clock = 24 hrs of the correct clock.
29 hrs of the clock = (24 x 6/145 x 24)hrs of the correct clock = 28 hrs 48 min of the correct clock.
The correct time = 28 hrs 48 min after 8 am.
Hence, the original time is 48 minutes past 12.
Question 5 |
A time of a clock is set 3.40. Find out the angle that is formed by both hour hand and minute hand:
120 degrees
| |
135 degrees
| |
140 degrees | |
130 degrees |
Discuss it
Question 5 Explanation:
The hour hand covers the angle 360 degrees in 12 hrs.
So, the angle is covered by it in 11/3 hrs = (360/2 x 11/3) degrees = 110 degrees .
The minute hand covers the angle in 360 degrees in 60 min.
So, the angle is covered by it in 40 min = (360/60 x 40) degrees = 240 degrees .
Hence, the required angle made by both hands = (240 - 110) degrees = 130 degrees .
Question 6 |
A clock shows 8:00 AM. When it is 2:00 PM, by what degree the hour hand rotates?
145º | |
160º | |
180º | |
175º |
Discuss it
Question 6 Explanation:
For 6 hrs duration hrs hand covered 6 hrs out of 12 hrs
When hrs hand covers 12 hrs it rotates for 360 degree
----------------------------6 --------------------- = (360/12)*6 = 180 degrees
When hrs hand covers 12 hrs it rotates for 360 degree
----------------------------6 --------------------- = (360/12)*6 = 180 degrees
Question 7 |
A clock shows 10:00 AM. When it is 4:00 PM, by what degree the hour hand rotates?
140º | |
152º | |
175º | |
180º |
Discuss it
Question 7 Explanation:
For 6 hrs duration hrs hand covered 6 hrs out of 12 hrs
When hrs hand covers 12 hrs it rotates for 360 degree
----------------------------6 --------------------- = 360/12)*6 = 180 degrees
Question 8 |
A clock shows 10:00 AM. When it is 10:00 PM, by what degree the hour hand rotates?
180 | |
175 | |
240 | |
360 |
Discuss it
Question 8 Explanation:
For 6 hrs duration hrs hand covered 12 hrs out of 12 hrs
When hrs hand covers 12 hrs it rotates for 360 degree
----------------------------12 --------------------- =(360/12)*12 = 360 degrees
Question 9 |
A clock shows 10:00 AM. What time it will be showing, if hrs hand rotates for 180 degrees?
1:00 PM | |
6:00 PM | |
4:00 PM | |
10:00 PM |
Discuss it
Question 9 Explanation:
When hrs hand rotates for 360 degree it covers 12 hrs
--------------------------------- 180 --------------------- 6 hrs
So the time will be: 10:00 AM + 6 hrs = 4:00 PM
Question 10 |
A clock shows 06:00 AM. What time it will be showing, if hrs hand rotates for 360 degrees?
4:00 AM of next day | |
06:00 PM | |
04:00 PM | |
10:00 PM |
Discuss it
Question 10 Explanation:
When hrs hand rotates for 360 degree it covers 12 hrs
--------------------------------- 360 --------------------- 12 hrs
So the time will be: 06:00 AM + 12 hrs = 06:00 PM
There are 18 questions to complete.