Agricultural Engineering Gate 2020 Questions with Answer

Ques 14 GATE 2020

A hydraulic sprayer when operating at a speed of 10 km h⁻¹ and working pressure of 420 kPa covers a width of 4.5 m. The power requirement and efficiency of the pump are 0.75 kW and 70%, respectively. Out of total pump discharge, 10% is bypassed for agitation purpose. The working pressure is increased to 500 kPa. Assuming no change in the width of coverage, the application rate of the sprayer in L ha⁻¹ (round off to 1 decimal place) is _______.

Ques 15 GATE 2020

A tractor PTO operated rotary disc mower has 4 rotating discs and the width of cut of each disc is 60 cm without any overlap. The specific power losses to air, stubble and gear-train friction is 2.5 kW per meter of cutting width. The specific cutting energy requirement is 2.0 kJ m⁻². If the machine is operated at a forward speed of 6 km h⁻¹, the PTO power requirement in kW (round off to 2 decimal places) is _______.

Ques 16 GATE 2020

A chaff cutter is operated by an electric motor running at 1440 rpm. The speed reduction from motor to the main shaft of the cutting unit is 4:1. The feed rollers of 10 cm diameter each are driven by the main shaft through a suitable gear drive with a speed reduction of 15:1. If the chaff cutter has two knives, the theoretical length of cut chaff in mm (round off to 2 decimal places) is _______.

Ques 17 GATE 2020

A tractor drawn right-hand offset disk harrow experiences longitudinal and side soil reactions in the front gang as 3.0 kN and 2.5 kN, respectively as compared to 3.5 kN and 4.0 kN in the rear gang. The longitudinal distance of centers of front and rear gangs are located at 2.5 m and 4.0 m, respectively behind the tractor hitch point. The required amount of offset of the disk harrow in m (round off to 2 decimal places) is _______.

Ques 18 GATE 2020

A bucket elevator for lifting parboiled paddy (bulk density = 840 kg m³) is operated at a linear speed of 2 m s^-1. The width of the bucket is 25.4 cm and its cross section is making a subtending angle of 75° at the centre of a circle having 12.7 cm radius. The space between two adjacent buckets on the elevator belt is 40 cm. If the buckets are filled to 80% of their volumetric capacity, the lifting capacity of elevator in kg min^-1 (round off to 2 decimal places) is _______.

Ques 19 GATE 2020

A self-propelled wheel does not have

Ques 20 GATE 2020

The sound pressure level on the operator's seat of a tractor is 80 dB. If the reference sound pressure is 2×10^-5 N m^-2, the root mean square (RMS) sound pressure in N m^-2 (round off to 2 decimal places) is _______.

Ques 21 GATE 2020

A two-wheel drive tractor with a total weight of 25 kN has a wheelbase of 2.2 m and its centre of gravity lies 0.7 m ahead of the centre of rear axle. A steady horizontal pull is applied at a drawbar hitch height of 0.5 m on a concrete surface such that the weight on front axle becomes 20% of static weight of the tractor. The coefficient of net traction (round off to 2 decimal places) is _______.

Ques 22 GATE 2020

The cooling system of a tractor fitted with diesel engine rejects 0.58 kW of heat per kW of brake power. It requires 0.16 L s⁻¹ of water per kW of heat rejection from the engine to maintain a temperature drop of 6 °C of water as it moves from the top of radiator to its bottom. If the engine develops 45 kW brake power, the required water flow rate in the radiator in L s⁻¹ (round off to 2 decimal places) is _______.

Ques 23 GATE 2020

A V-belt drive transmits 10 kW power at a belt velocity of 8 m s^-1. The angle of contact on the smaller pulley is 170° and groove angle of the pulley is 38°. The coefficient of friction between the pulley and the belt is 0.28 and the maximum permissible stress of the belt is limited to 4 MPa. Neglecting centrifugal effect of the belt, the minimum cross-sectional area of the V-belt in mm² (round off to 1 decimal place) is _______.

Ques 24 GATE 2020

A diesel engine when operates with biodiesel blend B20 (20% biodiesel and 80% diesel by volume) develops a brake power of 10 kW with a brake specific fuel consumption of 0.26 kg kW^-1 h^-1. If the density of biodiesel is 880 kg m³ and that of diesel is 850 kg m³, the amount of biodiesel required to run the engine for 3 hours in L (round off to 2 decimal places) is _______.

Ques 25 GATE 2020

At a speed of 1800 rpm, a centrifugal pump discharges 50 L s¹ at its best point of efficiency for a total head of 25 m. The specific speed of the pump in rpm (round off to 2 decimal places) is _______.

Ques 26 GATE 2020

The cooling system of a tractor fitted with diesel engine rejects 0.58 kW of heat per kW of brake power. It requires 0.16 L s⁻¹ of water per kW of heat rejection from the engine to maintain a temperature drop of 6 °C of water as it moves from the top of radiator to its bottom. If the engine develops 45 kW brake power, the required water flow rate in the radiator in L s⁻¹ (round off to 2 decimal places) is _______.