Find the area covered by minute hand of a clock from 12 to 3 if the radius of the clock is 14 cm
Answers
Step-by-step explanation:
Minute hand completes 60 minutes in 1 full circle i.e. 360°
So, 60 mins = 360°
Therefore 1 min = 6°
From 12 to 3 means that the minute hand has covered 15 minutes , which becomes that the minute hand has covered 15x6° = 90°
Area of the sector formed =
where alpha= angle in degrees
Area= 154 cm²
Given,
The radius of the clock = 14 cm
Minute hand travels from 12 to 3
To find,
The area covered by the minute hand.
Solution,
We can simply solve this mathematical problem by using the following mathematical process.
From 12 to 3, it is a time span of 15 minutes.
Now,
The whole circular clock = 360°
And,
The whole circular clock = 60minutes
Thus,
60 minutes of time span = 360°
1 minute of time span = 360°/60
15 minutes of time span = (360° × 15)/60 = 90°
So, the angular displacement of the minute hand = 90°
Now, we know that 90° angle is subtended by a quadrant (¼th part) of a circle.
So, we need to find out the area of a quadrant of the clock's circle, to calculate the area covered by the minute hand.
Thus,
Area covered by the minute hand = ¼ × (22/7) × (14)² = 154 cm²
Hence, the area covered by the minute hand is 154 cm².