Page 117 - Viva

Some watches and clocks have the second hand. It is the thinnest and the longest hand
of all the three hands on the clock. It moves very fast and covers one full circle across the

clock face in 60 seconds or one minute.
We can write ‘h’ for hours, ‘min’ for minutes and ‘s’ for seconds in short form to write
time.

Time in a.m. and p.m.

Telling time as 6 o’clock does not specify whether it is 6 o’clock in the morning or in the
evening. To avoid such confusions, we express time as a.m. or p.m.
• The time from 12 midnight to 12 noon is expressed as a.m. Here a.m. means ante

meridiem or before midday.
• The time from 12 noon to 12 midnight is expressed as p.m. Here p.m. means post
meridiem or after midday.

Let’s understand it this way.

1 day = 24 hours = 12 hours first half (a.m.) + 12 hours second half (p.m.)
For example, 6 o’clock in the morning is read as 6 a.m. and 6 o’clock in the evening is read
as 6 p.m.

Top Tips

• When the minute hand is at 3, it shows 15 minutes. It is called quarter past.
• When the minute hand is at 6, it shows 30 minutes. It is called half past.
• When the minute hand is at 9, it shows 45 minutes. It is called quarter to.

We do not write a.m. or p.m. with 12 o’clock. It is always written as 12 noon or 12 midnight.

Look at the given example.

Example 3: Write the time shown in the clock.
Solution: The hour hand is between 4 and 5 where it has crossed
4 but has not reached 5. The minute hand is at 3 which
means 15 minutes. So, the time is 4:15 a.m. if it is

morning, or 4:15 p.m. if it is evening. It can also be read
as quarter past 4.

Mental Maths
Write the following time in short.

(a) Quarter past 12 (in morning) ______________
(b) 15 minutes to 10 (in the evening) ______________
(c) Half past 3 (in the morning) ______________
(d) Quarter to 12 (in the evening) ______________

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