Question

A 2-wheel drive 35 HP tractor has 1.5 m rear wheel diameter. The engine runs at 1200 rev/min. the total reduction of speed is 30:1. Find the travelling speed of tractor in km/h.

(a) 12.09 kmh^-1

(b) 11.31 kmh^-1

(c) 14.90 kmh^-1

(d) 9.99 kmh^-1

This question was posed to me in unit test.

This intriguing question comes from Traction and Traction Theory in division Farm Tractor of Farm Machinery

Answer 1

The correct choice is (b) 11.31 kmh^-1

For explanation: P = \(\frac{2πNτ}{60} \)

τ = \(\frac{35*746*60}{2π*1200}\) = 207.776 Nm

On each axle = 207.776/2 = 103.88 Nm

V = \(\frac{πDN}{60} = \frac{π*1.5*1200}{30*60}\) = 3.14 ms^-1*5/18 = 11.31 kmh^-1