Vehicle Speed Calculator

Vehicle Speed Equation:

\[ \text{Speed} = \frac{\text{RPM} \times 60 \times 2 \pi r}{\text{Gear Ratio}} \]

Vehicle Speed:

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1. What is the Vehicle Speed Equation?

The Vehicle Speed Equation calculates the speed of a vehicle based on engine RPM, wheel radius, and gear ratio. It's fundamental in automotive engineering and vehicle performance analysis.

2. How Does the Calculator Work?

The calculator uses the Vehicle Speed Equation:

\[ \text{Speed} = \frac{\text{RPM} \times 60 \times 2 \pi r}{\text{Gear Ratio}} \]

Where:

\( RPM \) — Engine revolutions per minute
\( r \) — Wheel radius in meters
\( Gear Ratio \) — Transmission gear ratio (decimal)

Explanation: The equation converts rotational motion (RPM) to linear speed by accounting for wheel circumference and gear reduction.

3. Importance of Vehicle Speed Calculation

Details: Accurate speed calculation is crucial for vehicle design, performance tuning, and understanding the relationship between engine speed and actual road speed.

4. Using the Calculator

Tips: Enter RPM (engine speed), wheel radius in meters, and gear ratio (decimal). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How do I measure wheel radius?
A: Measure from the center of the wheel to the outer edge of the tire, or calculate it from tire size specifications.

Q2: What is a typical gear ratio?
A: Gear ratios vary widely but are typically between 2:1 and 5:1 for most passenger vehicles in high gear.

Q3: Why multiply by 60 in the equation?
A: This converts minutes to seconds, giving speed in meters per second.

Q4: How can I convert m/s to km/h or mph?
A: Multiply m/s by 3.6 for km/h or by 2.237 for mph.

Q5: Does this account for tire slip?
A: No, this calculates theoretical speed. Actual speed may vary due to tire slip, especially in acceleration or low-traction conditions.