A bicycle wheel whose radius is 30 cm covered a distancein 70 revolutions.how many kilometres was this distance
In a bicycle race kojo covered 250 m in 60s and yao covered 300 m in the same time interval. What is the ratio of yaos distance to Kojo's, simplest form
C = pi * d
C = 3.14 * 60
C = 188.4 cm
188.4 * 70 = 13,188 cm = 131.88 m = 0.13188 km
To find the distance covered by the bicycle wheel in kilometers, we need to calculate the circumference of the wheel and then multiply it by the number of revolutions.
The formula for the circumference of a circle is:
Circumference = 2πr
Where:
- Circumference is the distance around the circle
- π (pi) is a mathematical constant approximately equal to 3.14159
- r is the radius of the circle
Given that the radius of the bicycle wheel is 30 cm, we can substitute the value into the formula:
Circumference = 2π * 30 cm
To convert cm to km, we need to divide the circumference by 100,000 (since 1 km = 100,000 cm).
Circumference in km = (2π * 30 cm) / 100,000
Now, we need to calculate the distance covered by multiplying the circumference by the number of revolutions:
Distance = Circumference in km * Number of revolutions
Given that the number of revolutions is 70:
Distance = (2π * 30 cm) / 100,000 * 70
To obtain the final answer in kilometers:
Distance = (2 * 3.14159 * 30 cm / 100,000) * 70
Simplifying this expression gives:
Distance ≈ 0.13197 km
Therefore, the distance covered by the bicycle wheel is approximately 0.13197 kilometers.
To find the distance covered by the bicycle wheel in kilometers, we need to calculate the circumference of the wheel and then multiply it by the number of revolutions.
First, let's calculate the circumference of the wheel:
Circumference = 2 * π * radius
Given that the radius of the wheel is 30 cm, the circumference can be calculated as:
Circumference = 2 * 3.14 * 30 cm
Circumference ≈ 188.4 cm
Now, since the distance covered in one revolution is equal to the circumference, we can find the total distance covered by multiplying the circumference by the number of revolutions:
Total Distance = Circumference * Number of Revolutions
Given that the number of revolutions is 70, the total distance covered is:
Total Distance = 188.4 cm * 70 revolutions
Total Distance ≈ 13,188 cm
Since the distance is currently in centimeters, let's convert it to kilometers. There are 100,000 centimeters in a kilometer:
Total Distance in Kilometers = Total Distance / 100,000 km/cm
Total Distance in Kilometers ≈ 13,188 cm / 100,000 km/cm
Total Distance in Kilometers ≈ 0.13188 km
Therefore, the distance covered by the bicycle wheel is approximately 0.13188 kilometers.