Activity 1:

TIME

There are 24 hours in one day. There are 7 days in a week

There are 60 minutes in an hour. There are 12 months in a year

There are 60 seconds in a minute.

SHORT FORMS:

year = a

day = d

hour = h

minutes = min. (remember: m = metres!)

seconds = s

month = mo

week = wk

In this module we shall also come across tenths and hundredths of a second!

Analogue clocks and watches show twelve hours only. They do not indicate whether it’s morning or afternoon.

Every hour the long hand goes right round the circle once. It counts the minutes.

Figure 1

The long hand tells us the minutes.

The short hand tells us the hour.

The short hand takes twelve hours to go round the circle once. It tells us the hour.

Figure 2

Figure 3

Figure 4

Hands on: practical work

On the next page you will find two circles. Cut out the first one. Fold it in half. Open it and shade one half. Write PAST in the half on the right and TO in the half on the left. Now paste your cut-out on the circle below.

Table 2

TO

PAST

When we read the minutes, the first half of the circle shows minutes past the hour. When the long minute hand has gone halfway round the circle, we say it is half past the hour. The second half shows minutes to the next hour.

Now cut out the second circle on the “cutting page” page. Fold it in half and in half again. Open the circle and draw dotted lines on the folds. We have divided the hour into 4 quarters. So we get a quarter past the hour and a quarter to the next hour. Write A QUARTER PAST on the right side and A QUARTER TO on the left side and paste your cut-out on the circle below.

Table 3

A QUARTER TO

A QUARTER PAST

for cutting out

Table 4

Read the instructions very carefully; be sure you understand before you do each step.

Now we are going to write in the hours on the clock face. On the next page there are two more circles for you to cut out. Cut out the first one. Fold it in half. Fold it in half again. Do not open it. Now, fold the quarter in three (like an ice-cream cone). Can you predict how many parts there should be when you open it?

Figure 5

Yes, there should be 12 marks. Start with the top mark and label it inside the circle: 12. Then work clockwise and number each fold in the circle. (Your spaces between each number should be accurate because you made folds.) You have now written in the hours. Mark each fold at the edge of the circle and write in the number of the hour. (The first one has been indicated.) Paste it on the first circle on this page.

Figure 6

Now (on the cutting page) cut out the second circle. Mark in the hours as you did in the previous circle. Now you are going to mark in the minutes. There are 60 minutes in an hour, so how many minutes will there be between the numbers? Yes, 5, i.e. 5 spaces. Put little marks to show them and paste the circle on top of circle number 4. You have made an analogue clock face.

For cutting out

Table 5

TEST YOUR SKILLS: ANALOGUE CLOCKS

Figure 7

Figure 8

Figure 9

Figure 10

2.2 17 minutes to 10

(Did you remember that the hour hand is also moving, very slowly?)

Figure 11

2.3 a quarter to four

Figure 12

2.4 twelve o’clock

Analogue clocks cannot tell us whether it is morning or afternoon. We have to say it is 9 o’clock in the morning, or 4 o’clock in the afternoon. We use the following short forms:

a.m. = in the morning

p.m. = in the afternoon

Example:

A short way of writing 42 minutes past 10 o’clock in the morning is: 10.42 a.m. A short way of writing 36 minutes past 6 o’clock in the evening is: 6.36 p.m.

Activity 2:

This clock says 35 minutes past 8 o’clock in the morning (the 08 is less than 12).

Midnight would be 24:00.

One minute past midnight may be written as 00:01 or 24:01.

Noon or midday would be 12:00.

One minute past noon would be 12:01.

1. Write as digital time:

Study this example of a digital clock:

16:15

It shows the time, 4.15 p.m.

2.Now read the time on the analogue watch and write it correctly on the digital watch (in the frame on the right):

2.1

Figure 13

(in the morning)

2.2

Figure 14

(afternoon)

3. Draw hands on the analogue clock face to show the same time as is shown on the digital clock. Then write the time below the analogue clock to indicate if it is morning or afternoon. (Use the short form.)

Figure 15

13.50

Figure 16

09.10

An international clock is based on the same idea as the digital clock.

This clock also works from midnight to midnight.

The half of the clock face on the right shows time before noon (midday).

The left half shows time from noon to midnight.

Figure 17

4.By looking at this clock, how would you know that the time shown on it is in the morning?

A Stop-watch.

We use this at swimming galas and athletics and other sports events because we have to measure decimal fractions of a second!

5. Write the time that is shown in the frame:

5.1 Swimming: freestyle relay: 4 x 25m:

5.2 Athletics: 1500m:

Activity 3:

To solve problems involving calculation and conversion between the appropriate units of time [LO 4.2]

1. The annual Athletics meeting was held at school. The girls’ times in the 100 sprint were as follows:

Joy 14,9 seconds

Doreen 15,2 seconds

Petra 14,7 seconds

Kathleen 14,6 seconds

Marie 14,8 seconds

Barbara 15,5 seconds

1.1 Who won the race?

1.2 Explain why you give this answer.

1.3 What was the difference between Kathleen and Barbara’s times?

2. Mother puts a chicken into the oven to roast at 11:50. It takes an hour and ten minutes to roast. When will she take it out of the oven?

Remember: there are 24 hours in a day.

There are 60 minutes in an hour.

There are 60 seconds in a minute.

3. Flight 502 leaves East London at 13:10 and arrives at Johannesburg at 15:30. Flight 504 leaves East London at 19:35 and arrives at Johannesburg at 21:50.

3.1 Did the planes arrive in the morning, afternoon or evening?

Flight 502 ___________ Flight 504___________.

3.2 Which flight was the faster, and how much faster than the other one was it? Write down your calculations clearly, step by step.

. 4. The workers in a car factory start work at 8 a.m. They work until 5 p.m. with a lunch break of one hour and two tea breaks of ten minutes each. For how long do they work each day?

Months of the year – old rhyme:

Thirty days have September, April, June and November;

All the rest have thirty-one,

Excepting February alone, which has twenty-eight days clear,

And twenty-nine in each Leap Year!

5. When we write dates the short way, we write the year, the month and then the day, e.g. 2003: 01: 24 (24 January 2003)

The school year was as follows:

5.1 Write the date of the first day of the second term in full (the long way).

5.2 Write the date of the last day of the fourth term in full (the long way).

5.3 How long was the holiday between the first and second terms? Give your answer in weeks and days.

5.4 How long was the holiday between the second and third terms? Write down statements to show how you calculated this and give your answer in weeks and days.

5.5 How long was the holiday between the third and fourth terms? Give your answer in weeks and days.

6. Hannes is a keen fisherman. He was studying high tides because he was planning to go fishing off the rocks in the June holidays. Study this extract from the Table of High Tides in Cape Town and answer the questions that follow.

6.3 High tide at Knysna is 43 min. later. When is the morning high tide at Knysna on 30 June?

6.4 How much time goes by between the morning high tide and the afternoon high tide on 28 June?

When we add or subtract time, remember that we are working with hours, minutes and seconds.

60 seconds = 1 minute

60 minutes = 1 hour

Example: 1h 45min.+ 2h 36min. You will think of your own way to do this.

One way might be:

1h 45min. +2h 36min. = 3h 81min. (Notice: there is 1h hidden in those minutes.)

= 4h 21min.

7. Calculate the answers and write down your calculations:

7.1 53 min. and 48 sec. + 14 min. and 34 sec

7.2 14 h 25 min. － 7 h 36 min.

Activity 4:

To describe and illustrate ways of measuring and representing time in different cultures throughout history [LO 4.4]

ASSIGNMENT (RESEARCH-BASED)

Your educator will help you to find reference books or take you to the library when you need information in this Assignment.

1. Read the following information.

People in the Ancient World did not have clocks and watches as we know them, but they did try to measure time. Some of their instruments for measuring time included: a sun dial; a water clock; a candle clock; burning oil and an hour-glass. Some of them were not very accurate.

2. Look up information in reference books or on the computer to find out what these instruments looked like and how they worked. Also try to find out which people used them and where they lived.

3. Choose four of the instruments named in number 1. Draw them and label each drawing clearly.

4. Explain how any two of them worked.

5. Make either a water clock or a candle clock (or one of the others) and show it to the class. Explain to the class how it works.

6. In the table below write down which people used each of the clocks you have drawn and where they lived:

7. Explain why these ancient instruments were not always very accurate. Write your answer below.

8. Try to think of a link between one of them and a modern instrument which we use. Write down your answer .

ACTIVITY 1

1.1 2

1.2 5

1.3 7

Practical work

TEST YOUR SKILLS

1.1 20 to 11 or 10.40

1.2 9.25 or 25 past 9

2 Drawing hands on clock faces (see module)

ACTIVITY 2

1.1 05:10

1.2 16:20

1.3 21:45

1.4 00:57 or 24:57

2.1 06:45

2.2 16:10

3.1 Drawing on clock-face: ten to two in the afternoon

3.2 Drawing on a clock-face: ten past nine in the morning

4. Morning; the hour hand is on the right side of the clock-face; in the afternoon it would be on the left side of this clock-face.

5.1 1 min. 17,53s

5.2 5 min. 56,01s

ACTIVITY 3 problems involving time

1.1 Kathleen

1.2 Her time is the shortest

1.3 0,9s

2. 13:00 or 1 p.m

3.1 Flight 502: afternoon; Flight 504: evening

4. 7 h 40 min.

5.1 8 April 2003

5.2 5 December 2003

5.3 10 days

5.4 3 weeks 3 days

5.5 1 weeks 2 day

(Note: from morning high tide to afternoon high tide on the same day the time seems to decrease by 1min.each day, but not on 3 July.)

7.1 1h 8 min. 22 s.

7.2 6 h 49 min.

ACTIVITY 4 assignments

1. Read

2. Look up information

3.1 Drawings

3.2 Practical and oral

3.3 Own – practical and oral

3.4 Own – complete table

4. They could not measure seconds and parts of seconds; outside conditions (e.g. wind) influenced the instruments.

5. hour-glass; egg-timer