RULES TO LEARN

60 seconds = 1 minute

60 minutes = 1 hour

24 hours = 1 day

7 days = 1 week

2 weeks = 1 fortnight ("fourteen nights")

365 days = 1 year

366 days = 1 leap year (every 4 years e.g. the years 2012, 2016)

52 weeks - 1 year

26 fortnights = 1 year

12 months = 1 year

10 years = 1 decade

100 years = 1 century

1000 years = 1 millennium

60 seconds = 1 minute

60 minutes = 1 hour

24 hours = 1 day

7 days = 1 week

2 weeks = 1 fortnight ("fourteen nights")

365 days = 1 year

366 days = 1 leap year (every 4 years e.g. the years 2012, 2016)

52 weeks - 1 year

26 fortnights = 1 year

12 months = 1 year

10 years = 1 decade

100 years = 1 century

1000 years = 1 millennium

MNEMONIC - DAYS OF EACH MONTH

Thirty days have September

April, June and November.

All the rest have 31

Except February

That, when comes the time

In leap year, has twenty-nine.

Thirty days have September

April, June and November.

All the rest have 31

Except February

That, when comes the time

In leap year, has twenty-nine.

**Converting large unit to small unit (Multiply)**

10 minutes = 600 seconds

2 years = 104 weeks

3 weeks = 21 days

5 fortnights = 70 days

3 decades = 30 years

**Converting small unit to large unit (Divide)**

30 minutes = 30 ÷ 60 = 0.5 hour

45 minutes = 45 ÷ 60 = 0.75 hour

12 hours = 12 ÷ 24 = 0.5 day

13 weeks = 13 ÷ 52 = 0.25 year

30 years = 30 ÷ 100 = 0.3 century

This first ever photograph was taken by **Louis Daguerre**, an artist and physicist, in Paris in 1838.
Only 3 people can be seen in his photograph, but because Daguerre used **Time Lapse Photography**, there would have been many more
people moving in and out of view over the 15 minutes that the photographic plate was exposed.

You can create your own time lapse photographs with an ordinary camera by lengthening the exposure time. Try to make a "ghost" photograph by asking a person to stay still in front of the camera for about five seconds and then slowly moving out of view.

Complete these time conversions.

**Q1.** 15 minutes = hour
**Q2.** 20 hours = minutes
**Q3.** 1 day = minutes
**Q4.** 72 hours = days
**Q5.** 3 fortnights = days

**Answers**
**A1.** 0.25
**A2.** 1800
**A3.** 1440
**A4.** 3
**A5.** 42

The **Summer Solstice (Mid-summer)** occurs on the day of the year with the **most number of hours of daylight**.
In the northern hemisphere, this occurs on June 20th or 21st. In the southern hemisphere, this happens on December 21st or 22nd.
Similarly, the **Winter Solstice (Mid-winter)** has the **least number of hours of daylight**.
In the northern and southern hemispheres respectively, this occurs on December 21st or 22nd and June 20th or 21st.

An **Equinox** has **equal number of hours of daylight and dark**. The northern hemisphere's **Spring Equinox** is March 20th or 21st.
The southern hemisphere's Spring Equinox is September 22nd or 23rd.
The **Autumnal (Fall) Equinox** is September 22nd or 23rd in the northern hemisphere and March 20th or 21st in the southern hemisphere.