Question

the minute of a hand clock is 21 cm long. the distance moved by the tip of the minute hand in 1 hour is

Answer 1

To conplete 360°, minute hand neees 1hour

So

60minute = 360°

The length of minute hand will be the radius.

The area swept = π(r)²

= 22/7 × 21×21
= 1386 cm²

Answer 2

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$\large \bf \: GIVEN :-$

As we know, Minutes hand completes 1 rotation in 1 minute

So,

➞ Number of rotations completes in 20 minutes = 20

➞ The minute hand of a clock is 21 cm.

TO FIND :-

➞ The distance moved by the tip of the minute hand in 1 hour.

$\large\bf{\underline{\red{SOLUTION:-}}}$

Circumference of clock -

$\large \bf= 2\pi r$

$\large \bf = 2 \times 2 \times 21$

$\large \bf = 132cm$

Distance traveled in 1 rotation = 132 cm

Distance traveled in 20 rotations -

$\large \bf \: = 132 \times 20$

$\large \bf = 2640$

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