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A watch which gains 5 seconds in 3 minutes was set right at 7 a.m. In the afternoon of the same day, when the watch indicated quarter past 4 o'clock, the true time is:
- a)
- b)4 p.m.
- c)
- d)
Correct answer is option 'B'. Can you explain this answer?
a)
b)
4 p.m.
c)
d)
|
Aditya Kumar answered |
Time from 7 a.m. to 4.15 p.m. = 9 hours 15 min = 37/4 hours
3 min 5 sec of this clock = 3 min. of the correct clock.
⇒ 37/720 hours of this clock = 1/20 hours of the correct clock
⇒ 37 hours of this clock = (1/20 x 720/37 x 37/4) hours of the correct clock.
= 9 hours of the correct clock.
∴ The correct time is 9 hours after 7 a.m. i.e., 4 p.m
3 min 5 sec of this clock = 3 min. of the correct clock.
⇒ 37/720 hours of this clock = 1/20 hours of the correct clock
⇒ 37 hours of this clock = (1/20 x 720/37 x 37/4) hours of the correct clock.
= 9 hours of the correct clock.
∴ The correct time is 9 hours after 7 a.m. i.e., 4 p.m
The reflex angle between the hands of a clock at 10.25 is:- a)1800
- b)
- c)1950
- d)
Correct answer is option 'D'. Can you explain this answer?
a)
1800
b)
c)
1950
d)
|
Raksha Choudhary answered |
Angle traced by hour hand in 125/12 hrs = 
Angle traced by minute hand in 25 min =
∴ Reflex angle = 3600 -
Angle traced by minute hand in 25 min =
∴ Reflex angle = 3600 -
.
- a)A
- b)B
- c)C
- d)D
Correct answer is option 'C'. Can you explain this answer?
a)
A
b)
B
c)
C
d)
D
|
Vikram Kapoor answered |
15 past 5 means quarter past 5 = (5:15)
⇒ (11*15 - 60*5)/2 = 67.5
⇒ (11*15 - 60*5)/2 = 67.5
.
- a)A
- b)B
- c)C
- d)D
Correct answer is option 'B'. Can you explain this answer?
a)
A
b)
B
c)
C
d)
D
|
Pragya Satiwal answered |
Opposite time of 5 w.r.t to right angle is 8 then 8*60/11=480/11 so that time will be 480/11 min. past 5
The angle between the minute hand and the hour hand of a clock when the time is 4.20, is:
- a)00
- b)100
- c)50
- d)200
Correct answer is option 'B'. Can you explain this answer?
a)
00
b)
100
c)
50
d)
200
|
Pooja Shah answered |
The angle between hour and minute hand in 4:20 is 10 degrees.
For a minute, the hour hand rotates by 30/60 = 1/2 degrees.
hence, for 20 minutes it rotates by an angle of 20*1/2 = 10 degrees.
For a minute, the hour hand rotates by 30/60 = 1/2 degrees.
hence, for 20 minutes it rotates by an angle of 20*1/2 = 10 degrees.
Practice Quiz or MCQ (Multiple Choice Questions) with solution are available for Practice, which would help you prepare for "Clocks" under Logical Reasoning. You can practice these practice quizzes as per your speed and improvise the topic. The same topic is covered under various competitive examinations like - CAT, GMAT, Bank PO, SSC and other competitive examinations. Q. How many times in a day, the hands of a clock are straight?- a)22
- b)24
- c)44
- d)48
Correct answer is option 'C'. Can you explain this answer?
Practice Quiz or MCQ (Multiple Choice Questions) with solution are available for Practice, which would help you prepare for "Clocks" under Logical Reasoning. You can practice these practice quizzes as per your speed and improvise the topic. The same topic is covered under various competitive examinations like - CAT, GMAT, Bank PO, SSC and other competitive examinations.
Q. How many times in a day, the hands of a clock are straight?
a)
22
b)
24
c)
44
d)
48
|
Raghavendra Sharma answered |
In 12 hours, the hands coincide or are in opposite direction 22 times.
Therefore, In 24 hours, the hands coincide or are in opposite direction 44 times a day.
A clock is started at noom. By 10 mimutes past 5, the hour hand has turned through:
- a)1450
- b)1500
- c)1550
- d)1600
Correct answer is option 'C'. Can you explain this answer?
a)
1450
b)
1500
c)
1550
d)
1600
|
|
Maya Menon answered |
Angle traced by hour hand in 12 hrs = 360º.
Angle traced by hour hand in 5 hrs 10 min. i.e., 31/6 hrs
= (360/12*31/6)°
= 155º
Angle traced by hour hand in 5 hrs 10 min. i.e., 31/6 hrs
= (360/12*31/6)°
= 155º
.
- a)A
- b)B
- c)C
- d)D
Correct answer is option 'B'. Can you explain this answer?
a)
A
b)
B
c)
C
d)
D
|
|
Afruyash answered |
2pm on Wednesday
.
- a)A
- b)B
- c)C
- d)D
Correct answer is option 'D'. Can you explain this answer?
a)
A
b)
B
c)
C
d)
D
|
Future Foundation Institute answered |
When the hands of the clock are in the same straight line but not together, they are 30 minute spaces apart.
At 7 o'clock, they are 25 min. spaces apart.
Minute hand will have to gain only 5 min. spaces.
55 min. spaces are gained in 60 min.
5 min. spaces are gained in
∴ Required time =
min. past 7.
At 7 o'clock, they are 25 min. spaces apart.
Minute hand will have to gain only 5 min. spaces.55 min. spaces are gained in 60 min.
5 min. spaces are gained in
∴ Required time =
min. past 7.An accurate clock shows 8 o'clock in the morning. Through how may degrees will the hour hand rotate when the clock shows 2 o'clock in the afternoon?- a)154°
- b)180°
- c)170°
- d)160°
Correct answer is option 'B'. Can you explain this answer?
An accurate clock shows 8 o'clock in the morning. Through how may degrees will the hour hand rotate when the clock shows 2 o'clock in the afternoon?
a)
154°
b)
180°
c)
170°
d)
160°
|
Shivam Basu answered |
We know that angle traced by hour hand in 12 hrs = 360°
From 8 to 2, there are 6 hours.
Angle traced by the hour hand in 6 hours
= 6x(360/12)=180oAt 3:40, the hour hand and the minute hand of a clock form an angle of- a)135°
- b)130°
- c)120°
- d)125°
Correct answer is option 'B'. Can you explain this answer?
At 3:40, the hour hand and the minute hand of a clock form an angle of
a)
135°
b)
130°
c)
120°
d)
125°
|
|
Pankaj Nambiar answered |
Angle between hands of a clock
When the minute hand is behind the hour hand, the angle between the two hands at
M
minutes past
H
'o clock
When the minute hand is ahead of the hour hand, the angle between the two hands at
M
minutes past
H
'o clock
What is the angle between the hands at 4.40?- a)95°
- b)100°
- c)120°
- d)110°
Correct answer is option 'B'. Can you explain this answer?
What is the angle between the hands at 4.40?
a)
95°
b)
100°
c)
120°
d)
110°
|
|
Amrutha Kumar answered |
Angle between hands of a clock
When the minute hand is behind the hour hand, the angle between the two hands at
MM
minutes past
HH
'o clock
When the minute hand is ahead of the hour hand, the angle between the two hands at
MM
minutes past
HH
'o clock
Here H = 4, M = 40 the minute hand is ahead of the hour hand. Hence the angle
A clock is set at 5 am. If the clock loses 16 minutes in 24 hours, what will be the true time when the clock indicates 10 pm on 4th day?- a)9.30 pm
- b)10 pm
- c)10.30 pm
- d)11 pm
Correct answer is option 'D'. Can you explain this answer?
A clock is set at 5 am. If the clock loses 16 minutes in 24 hours, what will be the true time when the clock indicates 10 pm on 4th day?
a)
9.30 pm
b)
10 pm
c)
10.30 pm
d)
11 pm
|
|
Madhavan Nambiar answered |
Time from 5 am to 10 pm on the 4th day
= 3 days 17 hours
= 3 × 24 + 17
= 89 hours.
Given that clock loses 16 minutes in 24 hours.
How many times will the hands of a clock coincide in a day?- a)24
- b)20
- c)22
- d)21
Correct answer is option 'C'. Can you explain this answer?
How many times will the hands of a clock coincide in a day?
a)
24
b)
20
c)
22
d)
21
|
|
Pankaj Nambiar answered |
The hands of a clock coincide 11 times in every 12 hours (Between 11 and 1, they coincide only once, at 12 o'clock).
12:00 am
1:05 am
2:11 am
3:16 am
4:22 am
5:27 am
6:33 am
7:38 am
8:44 am
9:49 am
10:55 am
12:00 pm
1:05 pm
2:11 pm
3:16 pm
4:22 pm
5:27 pm
6:33 pm
7:38 pm
8:44 pm
9:49 pm
10:55 pm
Hence the hands coincide 22 times in a day.
This is already given as a formula and it's is better to learn the answer by heart as 22 which can save time in competitive exams.(However you should know the theory behind).
A watch which gains uniformly is 2 minutes low at noon on Monday and is 4 min. 48 sec fast at 2 p.m. on the following Monday. When was it correct?
a) 2 p.m. on Tuesday- b) 2 p.m. on Wednesday
- c) 3 p.m. on Thursday
- d) 1 p.m. on Friday
Correct answer is option `B`. Can you explain this answer?
a) 2 p.m. on Tuesday
b) 2 p.m. on Wednesday
c) 3 p.m. on Thursday
d) 1 p.m. on Friday
|
Ishani Rane answered |
Time from 12 p.m. on Monday to 2 p.m. on the following Monday = 7 days 2 hours.
=170 hours.
The watch gains
= (2 + 4 x4/5)min
= 34 / 5 min.in 170 hrs.
Now,34/5 min are gained in 170 hrs.
2 min are gained in(170x 5/34 x2)hrs.
Watch is correct 2 days 2 hrs. after 12 p.m. on Monday
i.e., it will be correct at 2 p.m.on Wednesday.
A clock is started at noon. By 10 minutes past 5, the hour hand has turned through- a)155°
- b)145°
- c)152°
- d)140°
Correct answer is option 'A'. Can you explain this answer?
A clock is started at noon. By 10 minutes past 5, the hour hand has turned through
a)
155°
b)
145°
c)
152°
d)
140°
|
|
Saptarshi Chauhan answered |
We know that angle traced by hour hand in 12 hrs = 360°
Time duration from noon to 10 minutes past 5
= 5 hours 10 minutes
Hence the angle traced by hour hand from noon to 10 minutes past 5
Find the time between 4 and 5'o clock, when the two hands of a clock are 4 minutes apart?- a)
- b)
- c)
- d)
Correct answer is option 'A'. Can you explain this answer?
Find the time between 4 and 5'o clock, when the two hands of a clock are 4 minutes apart?
a)
b)
c)
d)
|
Dipika Gupta answered |
At 4 o' clock, the hands are 20 minute spaces apart.
To get the first 4 min spaces between the hands ,the minute hand has to gain 20 - 4 = 16 minute spaces over the hour hand.
To get the second 4 min spaces between the hands ,the minute hand has to gain 20 + 4 = 24 minute spaces over the hour hand.
In 60 minutes, minute hand gains 55 minute spaces over the hour hand.
Time taken for gaining 16 minute spaces by minute hand
While determining the boiling point of water, the teacher suggested adding some pumice stone pieces to the hard glass test tube containing water. This was done to :- a)avoid bumping
- b)avoid melting of the hard glass test tube
- c)prevent unnecessary loss of heat energy
- d)spread the heat uniformly.
Correct answer is option 'A'. Can you explain this answer?
While determining the boiling point of water, the teacher suggested adding some pumice stone pieces to the hard glass test tube containing water. This was done to :
a)
avoid bumping
b)
avoid melting of the hard glass test tube
c)
prevent unnecessary loss of heat energy
d)
spread the heat uniformly.
|
Radha Iyer answered |
Pumice stone is added to facilitate bubbles so that "Bumping." can be prevented. It frequently happens, especially when the distillation has to be carried out under greatly reduced pressure, that the liquid is liable to boil with bumping. Thus we can measure the boiling point of water more accurately.
At what time between 4 and 5 o'clock will the hands of a watch point in opposite directions?- a)
- b)
- c)
- d)
Correct answer is option 'C'. Can you explain this answer?
At what time between 4 and 5 o'clock will the hands of a watch point in opposite directions?
a)
b)
c)
d)
|
|
Madhavan Nambiar answered |
The two hands of a clock will be in the same straight line but not together between
HH
and
(H+1)(H+1)
o' clock at
Here H = 4. Hands of the watch will point in opposite directions at
The minute hand of a clock overtakes the hour hand at intervals of 65 minutes. How much a day does the clock gain or loss?- a)
- b)
- c)
- d)
Correct answer is option 'D'. Can you explain this answer?
The minute hand of a clock overtakes the hour hand at intervals of 65 minutes. How much a day does the clock gain or loss?
a)
b)
c)
d)
|
|
Pankaj Nambiar answered |
If the minute hand of a clock overtakes the hour hand at intervals of
MM
minutes of correct time, the clock gains or loses in a day by
Here M = 65. The clock gains or losses in a day by
Chapter doubts & questions for Clocks - CSAT Preparation 2025 is part of UPSC CSE exam preparation. The chapters have been prepared according to the UPSC CSE exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for UPSC CSE 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
Chapter doubts & questions of Clocks - CSAT Preparation in English & Hindi are available as part of UPSC CSE exam.
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