Question

a thread goes 100 around a wheel of radius 14 cm if the radius of wheel is increased to 20 cm then find the no. of rounds the same thread will make around the wheel

Answer 1

Answer: The number of rounds, the same thread will make around the wheel would be 70.

Step-by-step explanation:

Radius of the wheel, r= 14 cm

Circumference of the wheel= 2*pi*r= 2*22/7*14=88 cm

The length of thread used in 1 round of the wheel= circumference of the wheel=88cm

The length of the thread used in 100 round of the wheel= 100*88

= 8800 cm

When radius of the wheel is increased to 20 cm,

Circumference of the wheel= 2*22/7*20= 880/7 cm

The number of rounds the same thread will make around the wheel

= length of thread/circumference of new wheel

= 8800/(880/7)=10*7

=70