Question

The length of a minute hand of a wall clock is 8.4
cm, then the area swept by it in 15 minutes:

​

Answer 1

Length of the minute hand of a wall clock = 8.4 cm

Since clock hand move in a circle so the length of the clock will be radius here

So the radius of the clock = 8.4 cm

We know the clock hand takes 1 hour to complete one rotation of circle

So 15 minutes covers = 15/60 = 0.25 rotation (Since 1 hour = 60 minutes)

Area swept by minute hand in 15 minutes = 0.25(Circumference of the clock)

= 0.25 * (πr²)

= 0.25(22/7 * 8.4 * 8.4)

= 0.25(22 * 1.2 * 8.4)

= 0.25(221.76)

= 55.44 cm²

Therefore the area swept by minute hand is 55.44cm²