Clock Aptitude Formula, Clock Problem Shortcuts and Tricks
Clock Important Questions - Page 2
Clock Video Lecture - Page 3
Clock: The Face or dial of a watch is a circle whose circumference is divided into 60 equal parts, called minute spaces. A clock has two hands, the smaller one is called the hour hand or short hand while the larger one is called the minute hand or long hand.
Clock Important Formulas
- In 60 minutes, the minute hand gains 55 minutes on the hour hand
- In every hour, both the hands coincide once.
- The hands are in the same straight line when they are coincident or opposite to each other.
- When the two hands are at right angles, they are 15 minute spaces apart
- When the hand's are in opposite directions, they are 30 minute spaces apart
- Angle traced by hour hand in 12 hrs = 360°.
- Angle traced by minute hand in 60 min. = 360°.
- Too Fast and Too Slow: If a watch or a clock indicates 8.15, when the correct time , 8 is said to be 15 minutes too fast.
- On the other hand, if it indicates 7.45, when the correct time is 8, it is said to be 15 minutes too slow.
Solved Examples for Clock Problem
Question - 1: The angle between the minute hand and the hour hand of a clock when the time is 4 : 20
Solution: Angle traced by hour hand in hrs =
Angle traced by min. hand in 20 min. =
Required angle = (130 - 120)º = 10º.
Question - 2: How many times are the hands of a clock at right angle in a day?
Solution: In 12 hours, they are at right angles 22 times.
In 24 hours, they are at right angles 44 times.
Question -3: How many times in a day, are the hands of a clock in straight line but opposite in direction?
Solution: The hands of a clock point in opposite directions (in the same straight line) 11 times in every 12 hours. (Because between 5 and 7 they point in opposite directions at 6 o' clcok only).
So, in a day, the hands point in the opposite directions 22 times
Question - 4: At what time between 9 and 10 o'clock will the hands of a watch be together?
Solution: To be together between 9 and 10 o'clock, the minute hand has to gain 45 min. spaces. 55 min. spaces gained in 60 min.
45 min. spaces are gained in min
The hands are together at min past 9