Quantitative Aptitude · Reasoning

Time and Clocks

562 Questions

Time and clocks problems evaluate quantitative aptitude by testing concepts on clock gains, losses, and relative speeds of hands. Questions also cover global time zones and standard time calculations. These logical reasoning topics frequently appear in SSC and banking exams.

Clock gain or lossTime zonesAngle between handsStandard time calculationPrecise time measurement

Time and Clocks Questions

Multiple choice maths measuring time time in 24 hour clock time difference time

The minute hand of a clock overtakes the hour hand at intervals of 65 minutes. How much in a day does the clock gain or lose?

  1. Gains $\displaystyle 56 \frac{8}{77}$ minutes
  2. Loses $\displaystyle 32 \frac{8}{11}$ minutes
  3. Loses $\displaystyle 9 \frac{10}{143}$ minutes
  4. Gains $\displaystyle 10 \frac{9}{143}$ minutes
  5. Gains $\displaystyle 10 \frac{10}{143}$ minutes
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

In a correct clock, the minute hand gains 55 min. spaces over the hour hand in 60 minutes.

To be together again, the minute hand must gain 60 minutes over the hour hand.

55 minutes are gained in 60 min.

60 min. are gained in [(60/55) * 60] min = $65\dfrac { 5 }{ 11 } $min.

But they are together after 65 min.

Therefore, gain in 65 minutes =  $65\dfrac { 5 }{ 11 } -60=\dfrac { 5 }{ 11 } $ min.

Gain in 24 hours = $\dfrac { 5 }{ 11 } * \dfrac { 24*60 }{ 65 } $ = 1440/143 min.

Therefore, the clock gains $(10 + 10/143 )$ minutes in $24$ hours.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

A man sets his watch by the noon whistle of a factory at a distance of $1.5 km.$ Then the number of seconds his watch slower than the clock of the factory (velocity of sound $= 332 m/s$) is 

  1. $4.52 sec$
  2. $5.35 sec$
  3. $2.18 sec$
  4. $3.76 sec$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

time taken for the whistle to reach the person is $\dfrac{d}{v}$
$=\dfrac{1.5\times 1000}{332}=4.52sec$
$\therefore$ delay of his clock is $4.52s$

Multiple choice physics superposition of waves coherence young's double slit experiment interference

The time of coherence is of the order of

  1. $10^{-4}s$
  2. $10^{-8}s$
  3. $10^{-6}s$
  4. $10^{-2}s$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a light source, a light wave(photon) is produced when an excited atom goes to the ground state and emits light.

The duration of this transition is $10^{-8}s$. Thus the emitted wave remains sinusoidal for this much time. This time is known as coherence time($\tau _c$).

Multiple choice physics superposition of waves coherence young's double slit experiment interference

The time of coherence is of the order of 

  1. $10^{-4}s$
  2. $10^{-8}s$
  3. $10^{-6}s$
  4. $10^{-2}s$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In a light source(photon) is produced when an excited atom goes to the ground state and emits light.

The duration of the transition is about $10^{-8}s$. Thus the emitted light remains sinusoidal for this much time. This is called the coherence time($\tau _c$).

Multiple choice maths calculating and mental strategies 3 finding percentage of a number how many in all? problems on percentage

What percentage of a day is six hours and 45 minutes?

  1. 7.218%

  2. 8.3%

  3. 28.125%

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A day is 24hrs.
 six hours and 45 minutes=
$6\frac { 45 }{ 60 } =6\frac { 3 }{ 4 } =\frac { 27 }{ 4 } Hrs$
So, % of a day=
$=\frac { 27 }{ 4*24 } \times 100$
$=\frac { 27 }{ 4*24 } \times 100=28.13%$
Answer (C) 28.125%

Multiple choice geography tides movements of ocean and sea water circulation of ocean water ocean water movement

What is the time interval of every high and low tide?

  1. 5 hour 25 minutes

  2. 6 hours 25 minutes

  3. 10 hour 25 minutes

  4. 12 hour 25 minutes
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

On an average, every place experiences high and low tide a day at an time interval of 12 hours 25 minutes. Since the earth completes its rotation in roughly 24 hours, every place should experience tide after 12 hours but this never happens. Each day tide delayed by 25 minutes because the moon also rotates on its axis while revolving around the earth. 

Multiple choice maths problems on measurement basic operations with same units operations involving units of length calculations choosing and converting between units conversion between different units conversion between units

Write following $12$ hour times into $24$ hour times.
$7:43$ pm

  1. $7:43$
  2. $19:43$
  3. $19:43$ pm
  4. $19:43$ am
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

To change a $pm$ time to $24$ hours time , you have to add $12 \ \ pm$ to the hours unless it is $12\ \ pm$ then the time remain unchanged .

$7:43\ \ pm=(7+12):43=19:43$
option $B$ is correct.

Multiple choice history heritage management conservation and preservation of heritage sources of modern history introduction to medieval india

Indian system views time in a _______ manner.

  1. Cyclic

  2. Linear

  3. Flexible

  4. None of them
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The manner in which the Indian system views time is cyclic. It is also referred to as Kalachakra. When one chakra completes, another starts. The completion of one of its cycle is known as Yuga. In this way, history has Yugas such as Tretayuga, Dwaparyuga etc.

Thus, the correct answer is A.

Multiple choice physics our solar system planets of the solar system solar system and sun introduction to solar system

The difference in the length of a mean solar day and a sidereal day is about

  1. $1$ minute
  2. $4$ minute
  3. $15$ minute
  4. $56$ minute
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Solar day is the time taken by earth to complete one rotation about its axis with respect to sun. Sidereal day is the time taken by earth to complete one rotation about its axis with respect to distant star. There is a difference of $4$ minutes between solar day and sidereal day. Solar day is longer as earth has to rotate greater angle to attain same position with respect to sun due to its own motion (revolution) round the sun. Its position with respect to distant star remains almost fixed.