Chapter 13.1 (Mathematics 5)

Measuring Time. Second. Minute

Identifying the Second as a Unit of Measuring Time

Group Activity 1

In groups of five:

  1. Let one pupil jump up and down at regular intervals for 10 seconds.
  2. Count how many jumps the pupil makes in 10 seconds.
  3. Count how many jumps the pupil can make in 1 second. Record the number of jumps for every member in the group.
  4. Carry out other similar activities with different pupils in the group.
  5. Discuss and share your results with other groups.

Note

  1. The second is the smallest unit of measuring time.
  2. The second is written in short as s.

Exercise A

  1. In groups of five, if 1 hand clap equals 1 second, time the following activities:

Activity

Time in claps

Time in seconds

a) Holding your breath

b) Jumping up and down 20 times

c) Singing the first stanza of the National Anthem in Kiswahili

d) Walking from the back of the classroom to the door

e) Reading a paragraph from an English book

  1. Use a stop-watch, a digital watch or a clock to time each activity in question 1 in seconds. Compare the time taken by each activity measured in hand claps with the time in seconds.

Relationship Between the Minute and the Second

Group Activity 2

In groups of five:

  1. Use a watch to count how many seconds make one minute.
  2. Discuss the relationship between the minute and the second.

Note

60 seconds = 1 minute

The minute is written in short form as min.

Exercise B

Min

1

2

3

4

5

6

Sec

 60 

B2

Do each of the following activities for 60 seconds:

  1. Jumping on the spot
  2. Rope skipping
  3. Swinging the hand
  4. Running a given distance