To determine the time it takes for the blades to make one revolution, we can use the formula for the period of circular motion. The period (T) is the time taken for one complete revolution. In this case, the speed of the blades (v) is given as 21 m/s, and the radius (r) is 0.053 m.
The formula to calculate the period is:
T = (2πr) / v
Let's substitute the given values into the formula:
T = (2 * π * 0.053 m) / 21 m/s
Calculating this expression:
T = (2 * 3.1416 * 0.053 m) / 21 m/s ≈ 0.159 s
Therefore, it takes approximately 0.159 seconds for the blades to make one complete revolution.