Recognising angles – text version

Activity 1 – Angles

See it

An angle is a measure of turning. It is written in degrees, which have the symbol of a small 'o' written as a superscript.

Turning a complete circle is written as 360 degrees.

Think about the angles between the hands of a clock at different times.

0° (zero degrees)

Image of a clock face withe the hour hand and minute hand both pointing to 12.

At 12 o'clock the hands are together and the angle between them is zero degrees.

30° (30 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on five.

If the minute hand moves to 5 minutes past the hour, and the hour hand stays pointing to the 12, the angle between the hands is 30 degrees.

Two other examples of where you might see an angle of 30 degrees are shown in the following images:

The angle between two spokes of a 12 spoked bicycle wheel.

The angle of a wedge shaped slice of cake.

45° (45 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on seven and a half minutes.

If the minute hand moves to seven and a half minutes past 12, and the hour hand stays pointing to the 12, the angle between the hands is 45 degrees.

Two other examples of where you might see an angle of 45 degrees are shown in the following images:

The angle between the top of the wall and the slope of the gable roof on a building.

The angle between the boom and the leading edge of the sail on a yacht.

60° (60 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on two.

If the minute hand moves to ten minutes past 12, and the hour hand stays pointing to the 12, the angle between the hands is 60 degrees.

Two other examples of where you might see an angle of 60 degrees are shown in the following images:

The angle on the corner of a triangular box of chocolate.

The angle between the ground and the side of a triangular shaped tent.

90° (90 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on three.

At a quarter past 12, the angle between the hands is 90 degrees. Notice that this is one quarter of an hour, and 90 degrees is one quarter of a full turn of 360 degrees.

Two other examples of where you might see an angle of 90 degrees are shown in the following images:

The angle between the side and the top of a briefcase.

The angle between the side and the top of a door way.

180° (180 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on six.

At a half past 12, the angle between the hands is 180 degrees. Notice that this is one half of an hour, and 180 degrees is one half of a full turn of 360 degrees.

270° (270 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on nine.

At a quarter to 12, the angle between the hands is 2700 degrees. Notice that this is three quarters of an hour, and 270 degrees is three quarters of a full turn of 360 degrees.

330° (330 degrees)

Image of a clock face withe the hour hand on 12 and the minute hand on 11.

If the minute hand moves to 5 minutes before the hour, and the hour hand stays pointing to the 12, the angle between the hands is 330 degrees.

Do it

This activity requires you to turn and raise a telescope to be able to view the planet Mars. Mars is located at 30 degrees east and 45 degrees above the horizon.