Introduction of clock

A clock is a circle with 360 degrees on it. It’s separated into 12 equal pieces with numbers ranging from 1 to 12. 360/12 = 30° for each section. One hour is when the minute hand completes a full round, i.e., covers 360°.

The hour and the minute hand are the two hands. Both hands move around the round dial. The hour hand is smaller compared to the minute hand and moves more slowly. The hour hand displays the time in hours, while the minute hand displays the time in minutes. We’ll look for some of the most basic clock formats are follow:

Dial: The dial of a clock is circular. The dial’s periphery is numbered 1 through 12 to indicate the hours in a 12-hour cycle. A dial’s diameter is divided into 60 equal minute spaces or 12 equal hour spaces.

Minute Spaces: The face or dial of a watch is circular divided into 60 equal pieces, known as minute spaces.

Hour Hand and Minute Hand: Clocks contain two hands, the smaller of which is known as the hour hand or shorthand, and the larger of which is known as the minute hand.

Second hand: On the circular dial, the second hand represents seconds. It rotates at a rate of one per minute.

Overlap: Once every hour, both hands will coincide.

Straight Line: When the hands are parallel or opposed to each other, they form a straight line.

 Formulas for  clock calculations

  1.       60-minute space = 360° = 1 hour
  2.       1 minute = 6 degrees = 1 minute
  3.       6° x 5 = 30° = 5 minutes in a 5-minute space
  4.       15-minute gaps apart at a right angle or perpendicular
  5.       22 times in 24 hours for a straight angle (1 day)
  6.       In 12 hours, the angle indicated by the hour hand equals 360°.
  7.       In 60 minutes, the angle drawn by the minute hand equals 360°.
  8.       Hour hand speed = 0.5 DPM (degree per minute)
  9.       30-minute interval apart at a straight angle or straight line (180°).
  10.   Minute hand speed = 6 DPM
  11.   At N o’clock, the angle of the hour hand from vertical is 30N.
  12.   44 times in 24 hours = right angle or perpendicular (1 day)

 

Important points and shortcuts of clocks calculations

  •         Every hour, the hands of both hands coincide once.
  •         They are 15-minute gaps apart when the two hands are at right angles.
  •         When the hands are parallel or opposite, they are in the same straight line.
  •         When the hands face each other, they are 30 minutes apart.
  •         In 60 minutes, the angle drawn by the minute hand equals 360°.
  •         In 12 hours, the angle indicated by the hour hand equals 360°.
  •         When a clock shows 8.15 and when the correct time is 8, it is 15 minutes early.
  •         On the other hand, if it says 7.45 when the true time is 8, it’s considered 15 minutes late.

 Clock calculations example

Q1. Between 4 o’clock and 5 o’clock, when are the clock hands opposite each other?

  1. A) At 4’O clock, 33(6/11)
  2. B) At 4’O clock, 54 (6/11)
  3. C) At 4’O clock ,44(6/11)
  4. D) At 4’O clock, 64 (6/11)

The minute hand is at 12 when the clock is at 4 o’clock. On the other hand, the minute hand crosses 4 at 20 minutes and then travels for another 30 minutes. As a result, it acquired a total of 20 + 30 = 50 minutes. As previously stated, the minute hand acquires 55-minute spaces above the hour hand for one hour. As a result, the minute spaces gained over the hour hand for 50 minutes are 50 x (60/55). This is the number 54 (6/11). A correct answer is an option (2).

 

Q2. In one hour, how many degrees does a hand cover?

Hour hand covers = 360/12 = 30° in one hour.

360/60 = 6° in one minute, minutes, and covers

 

Q3. It is now 2 p.m. How long does it take for the minute and hour hands to meet again?

Simply put, the minute hand moves faster than the hour hand. At 3 p.m., the minute’s hand must cover minutes to reach the hour’s hand, but the hour hand must cover “some distance” while the minute’s hand reaches the hour hand.

Now, how do you figure out “some distance”:

Multiply 10 minutes by 60/55 to get the total time.

10.90 (or 10 minutes 54 seconds) = 10 x 60/55 = 10.90 (or 10 minutes 54 seconds).

 Concept of the slow or fast open clocks

  •         When clocks read 9: 15 but the correct time is 9, it is considered to be 15 minutes off.
  •         On the other hand, if the clock reads 6:45 while the real-time is 7, it is considered 15 minutes late.

 Concept of angles

  •         The hour hand shifts at a rate of 0.5 degrees each minute (DPM). In 12 hours or 720 minutes, the hour hand completes a full round or 360 degrees.
  •         The minute hand shifts at a rate of 6 DPM. In 60 minutes, the minute hand completes a full round.
  •         The angle of hour hand from the vertical at ‘n’ o’clock is 30n.

 Conclusion

The open Clocks questionnaire is one of the essential topics in banking exams. It entails an in-depth logical examination and a high level of calculation to answer the problems correctly.