Question

The length of the minute hand of a wall clock is $14\mathrm{cm}$. The distance covered (in $\mathrm{cm}$ ) by the tip of the minute hand in 45 minutes will be___

Answer 1

Answer: 66

The radius of the circle $=14\mathrm{cm}$
So, circumference $=2\pi r=2\times \frac{22}{7}\times 14=88\mathrm{cm}$
Degree covered in 45 minutes
$=\frac{360^{\circ }}{60^{\circ }}\times 45=270^{\circ }$
Now, since distance covered in $1^{\circ }=\frac{88}{360^{\circ }}$
distance covered in $270^{\circ }=\frac{88}{360^{\circ }}\times 270^{\circ }$
$=66\mathrm{cm}$