A boy is cycling such that the wheels of the cycle are revoloving 140 times per minute.if the diameter of the wheel is 60 cm,calculate the speed per hour with which the boy is cycling. Find answer in km per hour
Step 1:
Circumference of the wheel = 2*pi*r
= pi*d
= 3.14 * 60 cm
= 188.4 cm
= 1.884 m
Step 2:
How much distance is being traveled each minute?
140 revolutions = 140 circumferences per minute
= (1.884*140) meters per minute
= 263.76 m per minute
= 4.4 m per sec
Step 3:
Convert m/s to km/h
=> 4.4 m/s
= 1.22 km/h
264 m/min * 60 min/hr = 15.8 km/hr
4.4 m/s * 3600 s/hr = 15.8 km/hr
final conversion went awry
To calculate the speed per hour at which the boy is cycling, we need to first calculate the distance traveled by the boy in one revolution of the wheel, and then convert it to kilometers. Then we can multiply that by the number of revolutions per minute and the number of minutes in an hour.
First, let's calculate the distance traveled in one revolution of the wheel. The distance traveled in one revolution is equal to the circumference of the wheel. The formula for the circumference of a circle is:
Circumference = π * diameter
Since the diameter of the wheel is given as 60 cm, the circumference will be:
Circumference = π * 60 cm
To find the speed per hour, we need to convert the distance traveled in one revolution from centimeters to kilometers. There are 100 centimeters in a meter, and 1000 meters in a kilometer:
Distance in km = (Circumference / 100) / 1000
Now we have the distance traveled in one revolution in kilometers. To find the speed per hour, we can multiply this distance by the number of revolutions per minute and the number of minutes in an hour:
Speed in km/h = (Distance in km * Revolutions per minute * Minutes per hour)
Given that the wheels are revolving 140 times per minute, and there are 60 minutes in an hour, the formula becomes:
Speed in km/h = ((Circumference / 100) / 1000) * 140 * 60
Now we can substitute the value of circumference into the formula and calculate the speed per hour.