This set of Farm Machinery Multiple Choice Questions on “Harvesting Equipments – Cutter Bar of Mower”.
1. Calculate the total time required to harvest 4 hectares of grass by means of a 2mm mower being operated at the speed of 4 km/h. Assume field efficiency of mower as 75%?
a) 4.67 hr
b) 5.67 hr
c) 6.67 hr
d) 7.67 hr
Answer: c
Explanation: Time=(frac{10*100*4}{4*2*75}) = 6.67 hr.
2. What horsepower will be required to pull 1.2 m mower working at the speed of 5 km/m length of the mower ad mechanical efficiency is 85%?
a) 1.56
b) 2.56
c) 3.56
d) 4.56
Answer: a
Explanation:
P=(frac{72*5*1000}{75*3600}) = 1.33 HP
Actual power = 1.33/0.85 = 1.56 HP.
3. How many hectares of grass per day of 15 hours can be cut by a mower being operated at the speed of 4.5 km/h and with 4 m cutter bar.
a) 20
b) 22
c) 27
d) 16
Answer: c
Explanation:
Fc=(frac{4.5*4}{10}) = 1.8 ha/hr
Area covered in 15 hours = 1.8*15 = 27 ha.
4. A mower has driven wheel of 60 cm diameter. The crank of mower makes 550 rpm, when it is driven by a tractor at a speed of 2 km/h. If speed ratio between the crank wheel and land wheel is changed to 27:1, calculate the increase in speed of mower to maintain the same speed of crank.
a) 0.20 km/h
b) 0.304 km/h
c) 1.402 km/h
d) 1.36 km/h
Answer: b
Explanation:
(frac{Nc}{Nl}=frac{27}{1} )
Nl=(frac{Nc}{27}=frac{550}{27}) = 20.38 rpm
Linear speed of mower, V = (frac{πDNc}{60} = frac{π*0.6*20.38}{60}) = 0.640 = (frac{0.640*3600}{1000}) = 2.304 km/h
Increase in speed = V2 – V1 = 2.304-2 = 0.304 km/h.
5. A 2m mower is operating at 3.5 km/h with an overall efficiency of 75%. Calculate the area covered by it in ha/h.
a) 0.525
b) 0.625
c) 0.725
d) 0.825
Answer: a
Explanation: Area covered=(frac{S*W*Ef}{10*1000}=frac{3.5*2*75}{10*100}) = 0.525 ha/h.
6. How many revolutions will each spindle of cotton picker make in the picking zone for a chain belt arrangement in which the speed of spindle is 1400 rpm and remains in the picking zone during 100 cm of forward travel.
a) 50
b) 21
c) 45
d) 11
Answer: b
Explanation:
Time required to move 100 cm = (frac{100*60}{4.5*10^3*100}) = 0.015 m
Number of revolutions in 0.015 min duration = 1400*0.015 = 21 revolutions.
7. A disc type mower is operated by PTO with 6 discs with a shaft of 0.4 m/disc. The specific energy required for cutting is 2.1 KJ/m2 and specific power losses due to air come stubble and gear train friction is 2 kw/m of cutting width. If the mower with tractor requires a propelling force of 2 KN the total power requirement for carrying out moving in Kw at forward speed of 3 km/h is ____
a) 10.67
b) 20.67
c) 30.67
d) 40.67
Answer: a
Explanation: Pcutting = 2.1*2.4*(frac{3*1000}{3600}) = 4.2 KW
Ppropelling = (frac{2*1000*3*1000}{3600}) = 1.67 KW
Ptotal = 4.8+4.2+1.67 = 10.67 KW.
8. The most common mower, amongst the following is ___________
a) Reciprocating mower
b) Lawn mower
c) Cylindrical mower
d) Horizontal mower
Answer: a
Explanation: A mower is a machine that cuts (mows) grass or other plants that grow on the ground. Mowing is different from reaping, which uses similar implements, but is the traditional term for harvesting grain crops. Sickle mowers, also known as reciprocating mowers, bar mowers, sickle-bar mowers, or finger-bar mowers, have a long bar on which are mounted fingers with stationary guard plates.
9. A gang mower is the group of ___________
a) 2 or more cylindrical mowers
b) 5 mowers
c) 2 mowers
d) 10 mowers
Answer: a
Explanation: A gang mower for garden tractors includes a frame, a hitch and either three, five or seven reel-type mower units attached to the frame.
10. In flail mower, the cutting section contains ___________
a) Cutter bar
b) Swinging knives
c) Fixed knives
d) Reciprocating fingers only
Answer: b
Explanation: A flail mower is a type of agricultural equipment that is used to deal with heavier grass or scrub. In flail mower, the cutting section contains Swinging knives.
11. In cutter bar of mower, the knife head is attached to the ___________
a) Knife back
b) Cutter end
c) Starting point of cutting edge
d) Reciprocating fingers
Answer: a
Explanation: Cutter bar of a mower is a bar with pointed guards along which the knife runs in a mowing machine or along which a sickle blade runs in a combine or binder.
12. In mower, the grass board is provided at the ___________
a) Cutter end
b) Knife end
c) Knife back
d) Reciprocating fingers
Answer: a
Explanation: A board attached to the end of a mowing machine cutter bar, positioned so that it turned back the falling grass cut near the end of the bar and kept it separated from the uncut grass.
13. In cutter bar of mower, the knife sections are revitted to the ___________
a) Knife back
b) Reciprocating fingers
c) Stationary bar
d) Cylindrical drum
Answer: a
Explanation: The bar rides on the ground, supported on a skid at the inner end, it can be tilted to adjust the height of the cut. A board, loaded with spring, at the outer end of the bar guides the cut hay away from the uncut hay.
14. In mower, the pitman transmits the motion to the ___________
a) Knife head
b) Knife middle
c) Knife back
d) Knife end
Answer: a
Explanation: A rod that transmits motion from one moving part to another, the rod connecting the crankshaft of a mower to a piston, also known as pitman.
15. Who invented the first lawn mower?
a) Albert Einstein
b) Buzz Aldrin
c) Edwin Budding
d) Yuri Gagarin
Answer: c
Explanation: The first lawn mower was invented by Edwin Budding in 1830 in Thrupp, outside Stroud, in Gloucestershire, England. Budding’s mower was designed mainly to cut the grass on sports grounds and extensive gardens and was granted a British patent on August 31, 1830.