Question

a bicycle wheel is 1m 26cm in diameter . calculate the number of rotations of the wheel needed to cover 1.98km

Answer 1

Diameter = 1m 26 cm = 1.26m
Radius = 1.26/2 = 0.63 m
Perimeter of wheel = 2πr
= 2 x 22/7 x 0.63 = 3.96 m
1.98km = 1980 m
Revolutions needed to cover 1.98km
= 1980/3.96
= 500
500 revolutions are needed to cover 1.98 km.

Answer 2

wheel rotate = 500 rotations

Explanation:

given data  

diameter = 1m 26 cm = 1.26 m  

distance = 1.98 km  = 1980 m  

solution

we get here radius first that is  

radius = diameter ÷ 2 .........1

radius = 1.26 ÷ 2  

radius = 0.63 m  

so here perimeter of wheel = distance travel by wheel 1 rotation  

Perimeter = 2 x π x r ..................2

put here value and we get  

Perimeter = 2 x 3.14 x 0.63  

Perimeter = 3.96 m

wheel 1 rotation = 3.96 m  

so wheel rotate in 1980 m is =  $\frac{1980}{3.96}$  

wheel rotate = 500  

learn more:  

number of rotations  

1, https://brainly.in/question/8139060