Farm Machinery Multiple Choice Questions on “Tractor Tyre and Front Axle”.
1. The comparative strength of tyre is indicated by ___________
a) Ply rating
b) Thickness
c) Materials of construction
d) Size and tyre width
Answer: a
Explanation: Tires provide a footprint, designed to match the weight of the vehicle with the bearing strength of the surface that it rolls over, providing a bearing pressure that will cause the deformation of the surface excessively.
2. In tyre size of 12-38’’, the number 38’’ represents _____
a) Sectional diameter of rim on which tyre is to be mounted
b) Ply rating
c) Sectional diameter
d) Strength of tyre
Answer: a
Explanation: The tyre size is defined as Width of tyre upon Ratio of tyre, Type of tyre, Diameter of rim to be used.
This could be understood by an example, 215/60R15 where, 215 is the width of the tyre in millimetres. 60 is the tyre profile. Radial construction is denoted by R. Diameter of the wheel rim in inches is 15.
3. Inflation pressure in rear wheel of tractor varies between ___________
a) 0.8-1.5 kg/cm2
b) 1.5-2.0 kg/cm2
c) 2.0-2.5 kg/cm2
d) 2.5-3.0 kg/cm2
Answer: a
Explanation: Cold inflation pressure is the pressure of tires when tires are warmed up and before the car is driven. The recommended cold inflation pressure is written on the owner’s manual and attached to the vehicle.
4. The useful life of pneumatic tyres under normal operating condition for drawbar works is about ___________
a) 10000 hrs
b) 6000 hrs
c) 2000 hrs
d) 1500 hrs
Answer: b
Explanation: Pneumatic tyre is a tyre made of reinforced rubber and filled with compressed air; used on motor vehicles, tractors and bicycles.
5. In traction, the front wheel acts as ___________
a) Drive wheel
b) Caster wheel
c) Steered wheel
d) Track wheel
Answer: c
Explanation: Traction is the grip of a tyre on a road or a wheel on a rail.
6. The term toe-in is associated to ___________
a) Front axle of tractor
b) Rear axle of tractor
c) Carburettor
d) Ignition chamber
Answer: a
Explanation: Toe-in is a slight forward convergence of a pair of wheels so that the wheels are closer together in front than from behind.
7. Ground clearance of tractor is measured under ___________
a) Maximum permissible load condition
b) Without loading condition
c) Normal loading condition
d) Medium loading condition
Answer: a
Explanation: Ground clearance is the amount of clear space between the lowest part of a vehicle’s frame and the ground.
8. During tractor running the tyre slippage can be controlled by ___________
a) Increase tractor speed
b) Decreasing load of tractor
c) Increasing co-efficient of traction
d) Decreasing pressure of tyre
Answer: c
Explanation: The force which can be used for traction divided by the weight on the running gear is known as the coefficient of traction:
Usable traction = coefficient of traction x normal force.
9. The angle between centre line of tyre and vertical line is called ___________
a) Caster angle
b) Camber angle
c) Tilt angle
d) Bearings
Answer: b
Explanation: Camber angle is the angle made by the wheels of a vehicle; it is the angle between the vertical axis of the wheels used for steering and the vertical axis of the vehicle viewed from the rear or front.
10. The wheel type tractor is not suitable for ___________
a) Low ground pressure
b) High ground pressure
c) Undulate land
d) Road transport
Answer: a
Explanation: Tractor is a self-propelled power unit having wheels for operation on agricultural implements and machines including trailers. Tractor engine is used as a main mover for active tools through PTO or belt pulley. Low ground pressure is not suitable for wheel type tractor.
11. Excessive vibration of tyre is ___________
a) Swinging
b) Wobbling
c) Repositioning
d) Slipping
Answer: b
Explanation: Wobbling is moving unsteadily in a particular direction.
12. Range 2° to 4° is of _______
a) Caster angle
b) Camber angle
c) King pin inclination
d) Slipping
Answer: b
Explanation: Camber angle is the angle between the vertical axis of the wheels used for steering and the vertical axis of the vehicle viewed from the rear or front. The range of Camber angle is 2° to 4.
13. If the inner and outer steering angles in a tractor are 9° and 9.8° respectively then for correct steering condition the value of the ratio of pivot axis spacing to travel length is equal to ____
a) 0.256
b) 0.525
c) 0.756
d) 0.990
Answer: b
Explanation: cot φ – cot θ = c/b
Cot 9 – cot 9.8 = c/b
c/b = 0.525.
14. A motor has a wheel base of 2.73 m and pivot centre of 1.065 m. the rear and front wheel track is 1.217 m. calculate turning circle radius of the outer front and inner rear wheels when the angle of inside lock is 40° and outside lock is 32°.
a) 7.25 m:4.18 m
b) 6.25 m: 2.18 m
c) 5.25 m: 3.18 m
d) 4.25 m: 1.18 m
Answer: c
Explanation:
Rf = (frac{b}{sinφ}+frac{a-c}{2}=frac{2.743}{sin32}+frac{1.217-1.065}{2}) = 5.25 m
Turning radius of inner radius wheel Rr = b cot φ – (a-c)/2 = 3.18 m.
15. When did tractors started using rubber tyres?
a) 1857
b) 1933
c) 1989
d) 2003
Answer: b
Explanation: By 1933, tractor companies offered models with rubber tires which were already mounted on rims. Blacksmith shops’ saw a growth in their business when they started retrofitting steel wheels to rubber ones. 95% of new tractors rode on rubber wheels by 1940.