Question

The diameter of the wheel of a car is 70cm how many revolutions will it take to travel 1.65km

Answer 1

hello,


1.65 km = 1.65 ×1000×100 cm
              = 165000 cm 
now,radius = diameter/2
           = 70/2
           =35 cm
now, circumference = 2π r
                                 = 2×(22/7)×35
                                 = 220 cm
it means, 220 cm = 1 revolution
       then, 165000 cm = 165000/220
                                   = 750 revolution

Answer 2

Given,

Diameter of wheel of car= 70cm

Hence, radius of wheel of car= 70/2

=35cm.(r)

Now, total distance to be travelled= 1.65km

=>1650m.

=>1650×100

=>165000cm.

So, According to the question---->>

No. of revolution×circumference = Total distance covered

=>n × 2π×r = 1650

=>n=(165000× 7)/22×35×2

=>n=750.

Hence, the car will take approximately 750 rotations to cover 1.65km or 1650m or 165000cm

Remember

Perimeter of the Circle = Circumference of circle

= 2π×r

1m= 100cm

1km= 1000m