List of top Farm Machinery Questions on Tractors and Power Tillers

A mouldboard plough is operated by a 2WD tractor with 6.0 kN pull. The ratio of lateral component to the longitudinal component of soil forces is 0.30, and the ratio of the vertical component to the longitudinal component of soil forces is 0.50. If the diameter of the driving wheels is 1.2 m and the rear axle rotates at 10 rpm, the drawbar power produced at 20% wheel slip is _________ kW. (Rounded off to 2 decimal places)
The height of the CG of a 4WD tractor with equal tread (1.25 m) in front and rear is 0.85 m. The tractor overturns during turning at a speed of 18 km.h\(^{-1}\). Neglecting the frictional forces on the tractor wheels, the turning radius is _________ m. (Rounded off to 2 decimal places)
The nominal radius of the rear wheels of a 2WD tractor is 0.5 m. The rolling radius of the tire is 6% less than the nominal radius. While conducting a field test, if the actual distance covered for 20 revolutions of the rear wheel is found to be 56 m, the rear wheel slip is _________% (Rounded off to 2 decimal places).
Front wheel pivot points of a 2WD tractor are 1.2 m apart. When making turn on a flat concrete surface, the inner front wheel makes 50$^\circ$ and the outer front wheel makes 35$^\circ$ steering angles. To ensure turning without front wheel skid, the wheel base of the tractor should be _________ m. (Rounded off to 2 decimal places)
A mouldboard plough is operated by a 2WD tractor with 6.0 kN pull. The ratio of lateral component to the longitudinal component of soil forces is 0.30, and the ratio of the vertical component to the longitudinal component of soil forces is 0.50. If the diameter of the driving wheels is 1.2 m and the rear axle rotates at 10 rpm, the drawbar power produced at 20% wheel slip is _________ kW. (Rounded off to 2 decimal places)
The height of the CG of a 4WD tractor with equal tread (1.25 m) in front and rear is 0.85 m. The tractor overturns during turning at a speed of 18 km.h\(^{-1}\). Neglecting the frictional forces on the tractor wheels, the turning radius is _________ m. (Rounded off to 2 decimal places)
Front wheel pivot points of a 2WD tractor are 1.2 m apart. When making turn on a flat concrete surface, the inner front wheel makes 50$^\circ$ and the outer front wheel makes 35$^\circ$ steering angles. To ensure turning without front wheel skid, the wheel base of the tractor should be _________ m. (Rounded off to 2 decimal places)
The nominal radius of the rear wheels of a 2WD tractor is 0.5 m. The rolling radius of the tire is 6% less than the nominal radius. While conducting a field test, if the actual distance covered for 20 revolutions of the rear wheel is found to be 56 m, the rear wheel slip is _________% (Rounded off to 2 decimal places).
While studying vertical motion imparted to the base of tractor seat, \( \theta \) (radian) is considered as rotation about tractor’s CG and \( R \) is considered as longitudinal distance from operator’s seat to the tractor’s CG. For a small value of \( \theta \), the term ‘\( R\theta \)’ represents the vertical motion resulting from tractor’s _________
A 4-stroke diesel engine can be operated with either diesel (HV = 45 MJ/kg) or biodiesel B20 (HV = 42.1 MJ/kg). Brake specific fuel consumption: diesel = 260 g/kWh, B20 = 310 g/kWh. For brake power = 20 kW, the change in brake thermal efficiency of the engine when B20 is used is \underline{\hspace{3cm}}.
A single disc clutch is used to transmit 10 kW power at 1400 rpm. The axial pressure = 0.07 N/mm\(^2\), coefficient of friction = 0.25, ratio of inner to outer radius = 0.8. If the uniform wear theory applies, the required face width of clutch lining is \underline{\hspace{3cm}}.
In a tractor seat system, the chassis frequency and seat suspension damping rate are 20 rad s\(^{-1}\) and 400 N m\(^{-1}\) s, respectively. The critical damping rate of the tractor seat system is 1600 N m\(^{-1}\) s. If the combined mass of the seat and operator is 80 kg, the transmissibility of vibration is \underline{\hspace{2cm}} (rounded off to 2 decimal places).
A power operated chaff cutter with a mean cutting radius of 0.25 m is fitted with two cutting knives and is rotating at 300 rpm. Thirty maize stalks with a mean diameter of 12 mm are fed through the throat at a time. The dynamic shear strength of the stalk is 0.05 N mm\(^{-2}\). The mass and radius of gyration of the flywheel (including knives) are 40 kg and 0.27 m, respectively. The total shaft power requirement in kW is \underline{\hspace{4cm}} (rounded off to 2 decimal places).
A two-wheel drive tractor with a total weight of 24 kN has a static weight distribution of 30% and 70% at the front and rear axles, respectively. When the tractor is operated on a level ground of pure sand, the maximum tractive force developed is 13 kN. If external weight of 1.5 kN is added to the rear axle, neglecting weight transfer, the change in maximum tractive force in kN is \underline{\hspace{4cm}}.
A vertical disc plough with 5 discs is operated at a depth of 0.15 m. The disc angle and disc diameter are \(40^\circ\) and 0.6 m, respectively. If overlap between two consecutive discs is 0.12 m at 0.15 m depth of cut, the total width of cut at the specified depth in m is:
In a 9 × 20 cm fluted roller type seed drill, each fluted roller is discharging 4.25 g of seed per revolution of fluted roller shaft. The fluted roller shaft rotates once for two complete rotations of the ground drive wheel of the seed drill. The rolling diameter of the ground drive wheel is 0.35 m. Considering no skid of the ground drive wheel, the seed rate in kg/ha is (take \(\pi = 3.14\)):
A field sprayer with 12 nozzles fitted to the boom at a spacing of 0.5 m is used for spraying at a height of 0.75 m from the ground. The angle of spraying is \(75^\circ\). If the height of spraying is reduced to 0.6 m, the change in swath in m is:
Considering declining balance method, the constant rate of depreciation at which the value of the tractor will come down to 50% of its purchase price at the end of 4th year (in percent) is \underline{\hspace{6cm}} (rounded off to 2 decimal places).
In a 4-stroke single cylinder diesel engine, the inlet valve opens at \(10^\circ\) before TDC and closes at \(40^\circ\) after BDC. The exhaust valve opens at \(25^\circ\) before BDC and closes at \(15^\circ\) after TDC. The percentage of time for which both valves remain closed in one engine cycle is
The torque available at maximum power developed by the tractor is \(150\ \mathrm{N\,m}\). If the reserve torque is \(20%\), the peak torque that can be developed by the tractor (in \(\mathrm{N\,m}\)) is
In rotary tiller, the total energy requirement for carrying out tillage will decrease if
The effectiveness of the turbocharger of a diesel engine increases when

An engine develops 42 kW brake power when it runs with B20 fuel (80% biodiesel and 20% diesel by volume) with a brake thermal efficiency of 24%. The heating value of the fuel is 46.15 MJ kg$^{-1}$ and its density is 0.845 kg L$^{-1}$. The fuel consumption of the engine in L h$^{-1}$ will be _____.\( \textit{[Round off to two decimal places]}\)

The root mean square acceleration for mechanical vibration of a tractor is 3.15 m s$^{-2}$ and its frequency is 80 Hz. The root mean square amplitude of the vibration in µm is _____. \(\textit{[Round off to two decimal places]}\)

The static weight on front and rear axles of a two-wheel drive tractor are 3 kN and 9 kN, respectively. The wheel-base of the tractor is 2.1 m and the tractor pulls a load of 7.5 kN. The perpendicular distance from the front wheel ground contact point to the line of pull is 680 mm. Neglecting the wheel contact off-set on the ground, the weight transfer onto the rear axle in kN is _____. \textit{[Round off to two decimal places]}