Question Bank • QB_FP_ADV_043 NAT • 2 Marks

Section 3: Farm Power

Tractors and Power Tillers

Subtopic: Tractor clutches and brakes

Question Statement:

A single-plate dry friction clutch in a tractor has friction linings on both sides ($n = 2$). The outer radius of the friction lining is $r_o = 150\text{ mm}$ and the inner radius is $r_i = 100\text{ mm}$. The total axial clamping spring force is $W = 3500\text{ N}$ and the coefficient of friction is $\mu = 0.30$. Assuming uniform wear theory ($r_m = \frac{r_o + r_i}{2}$), the torque transmitting capacity of the clutch in $\text{N}\cdot\text{m}$ is ________ (round off to 1 decimal place).

Answer Key:

262.5

Step-by-Step Solution & Explanation

``` Friction Clutch Torque Model (Uniform Wear): Outer radius: r_o = 0.15 m Inner radius: r_i = 0.10 m Axial force: W = 3500 N Friction surfaces: n = 2 mu = 0.30 ``` **Step-by-step Calculation:** 1. Mean radius of friction surface under uniform wear theory: $r_m = \frac{r_o + r_i}{2} = \frac{0.150 + 0.100}{2} = 0.125\text{ m}$ 2. Friction torque transmitting capacity ($T$): $T = n \times \mu \times W \times r_m$ $T = 2 \times 0.30 \times 3500\text{ N} \times 0.125\text{ m} = 2100 \times 0.125 = 262.5\text{ N}\cdot\text{m}$
← Previous (QB_FP_ADV_044) Next (QB_SUB_FP_BRK_001) →

Practice In Authentic CBT Exam Interface

Test your skills under authentic timed conditions with live scoring and AIR percentile ranking.

Launch CBT Mock Test