Areas related to Circles ncert solutions Chapter 12 Exercise 12.2 Question 3
3. The length of the minute hand of a clock is 14 cm. Find the area swept by the minute hand in 5 minutes.
We need to find area swept by minute hand clock in 5 minutes. In other words, we want to find area of the sector of circle.
Length of minute hand of circle = 14 cm which is radius of circle.
We do not know angle of sector yet. Lets find it.
In 60 minutes minute hand covers of angle.
In 1 minute, minute hand covers
In 5 minutes, minute hand covers
Area of sector of circle =
Area of sector =