When the minute hand moves by 30 minutes, it travels half of the clock face between 12 and 6. This is called a half turn. A half turn is the same as a straight angle.
Class 5 Mathematics Maths-Mela Angles as Turns
Class 5 Mathematics Maths-Mela Chapter 3 Angles as Turns question answer
If the minute hand moves by 30 minutes, it goes from 12 to 6 on the clock face. This distance is exactly half the circle, so the movement is called a half turn. A half turn makes a straight angle, which equals 180 degrees. Just like drawing a straight line, the hand points in the opposite direction from where it started.
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