12 hour and 24 hour clock
Time is measured using either the 12 hour clock or the 24 hour clock.
12 hour clock
The 12 hour clock notation uses am to indicate morning and pm to show afternoon and evening.
- am is the time from 12 midnight and before 12 noon.
- pm is the time from 12 midday and before 12 midnight.
For example
- 6.23 am is twenty three minutes past six in the morning.
- 7.45 pm is quarter to eight in the evening.
24 hour clock
The 24 hour clock does not require the use of am or pm and the day isn't divided into two, twelve-hour halves.
The whole day is represented by a set of twenty four hours. Afternoon is indicated by a number bigger than \(12\).
For example
- 6.23 pm becomes (6.23 + 12) = 18:23
- 7.45 pm becomes (7.45 + 12) = 19:45
The 24 hour clock always uses 4 digits, so for any time before 10:00 a zero is placed at the beginning.
For example
- 01:00 means 1.00am
- 13:00 means 1.00pm
- 04:00 means 4.00am
- 16:00 means 4.00pm
Question
Copy and complete the following table, then check your answers.
