# Gear ratio requirement (RPM --> km/h)

D.B0004

## Homework Statement

A vehicle having wheels with a diameter of 58cm, is powered by motors that have a maximum speed of 6024 rpm. Each motor is coupled to the wheel using a gear mechanism as shown in figure 2-14. Calculate the required gear ratio if the vehicle's maximum speed is 190.2 km/hr.

Note: Answer is a unitless value, correct upto two decimals.

## Homework Equations

No clue. C = 2 * PI * R?

## The Attempt at a Solution

I converted 6024 rpm to radians per second hoping I could do the same with hm/hr, but I do not know the radius of the tire? See photo attache for diagram. Thanks for help.

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## Homework Statement

A vehicle having wheels with a diameter of 58cm, is powered by motors that have a maximum speed of 6024 rpm. Each motor is coupled to the wheel using a gear mechanism as shown in figure 2-14. Calculate the required gear ratio if the vehicle's maximum speed is 190.2 km/hr.

Note: Answer is a unitless value, correct upto two decimals.

## Homework Equations

No clue. C = 2 * PI * R?

## The Attempt at a Solution

I converted 6024 rpm to radians per second hoping I could do the same with hm/hr, but I do not know the radius of the tire? See photo attache for diagram. Thanks for help.
... but you know the diameter of the wheel. How is diameter related to radius?...