Calculating the number of revolutions:

- First, we need to calculate the circumference of the wheel using the formula:
Circumference = 2 x π x radius
C = 2 x 3.14 x 7 = 43.96 cm

- Next, we convert the distance of 100km into centimeters since 1 km = 100,000 cm:
100km = 100,000 cm

- Now, we divide the total distance by the circumference of the wheel to find the number of revolutions:
Number of revolutions = 100,000 cm / 43.96 cm = 2271.37

- Since the number of revolutions must be a whole number, we round down to the nearest whole number:
Number of revolutions = 2271

Explanation:

- The wheel of the car with a radius of 7cm will make approximately 2271 revolutions in a distance of 100km. This means that the wheel will rotate 2271 times to cover a distance of 100km. This calculation is important for determining the overall distance traveled by the car and understanding the mechanical aspects of the vehicle's movement. The number of revolutions helps in calculating the wear and tear on the wheel, as well as the speed and efficiency of the car. It is a crucial factor in understanding the performance and functionality of the vehicle.