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RPM to MPH Formula:
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RPM to MPH conversion calculates the linear speed (in miles per hour) based on rotational speed (revolutions per minute) and wheel/tire diameter. This is particularly useful in automotive applications, bicycle speed calculations, and various mechanical engineering contexts.
The calculator uses the following formula:
Where:
Explanation: The formula calculates the circumference of the wheel, multiplies by RPM to get inches per minute, then converts to miles per hour.
Details: This conversion is essential for vehicle speed calculations, gear ratio optimization, speedometer calibration, and performance analysis in automotive and mechanical applications.
Tips: Enter RPM value (must be greater than 0) and wheel/tire diameter in inches (must be greater than 0). For accurate results, measure the actual rolling diameter of the wheel/tire combination.
Q1: Why is wheel diameter important in this calculation?
A: Wheel diameter directly affects the distance traveled per revolution. Larger wheels cover more distance per revolution than smaller wheels at the same RPM.
Q2: Can I use this calculator for bicycle speed calculations?
A: Yes, this calculator works for any rotating wheel application including bicycles, cars, motorcycles, and industrial equipment.
Q3: How accurate is this calculation?
A: The calculation is mathematically precise. Accuracy in real-world applications depends on accurate measurement of wheel diameter and accounting for factors like tire pressure and wear.
Q4: Does this account for gear ratios?
A: No, this calculation assumes a direct relationship between engine/axle RPM and wheel RPM. For vehicles with transmissions, you would need to account for gear ratios separately.
Q5: Can I convert MPH back to RPM with this formula?
A: Yes, the formula can be rearranged to calculate RPM from MPH: \( RPM = \frac{MPH \times (60 \times 12 \times 5280 / 63360)}{Diameter \times \pi} \)