Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 7th Semester (Seventh Semester) 2018-2019 NME 702 Automobile Engineering Question Paper
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B. TECH.
(SEM.VII) THEORY EXAMINATION 2018-19
AUTOMOBILE ENGINEERING
T ime: 3 Hours 5 T otal Marks: 100
Note: 1. Attempt all Sections. If require any missing data; then choose suitably.
2. Be precise in your answer. Draw neat diagrams wherever necessary.
SECTION A
1. Attempt all questions in brief. 2 x 10 = 20
a. De?ne ?Automobile? and classify Auto- vehicles from different aspects.
b. Write important events from history of an Automobile.
c. Explain the reason that why big tyres are used in rear of vehicles.
d. What are the various defects in clutch?
e. ?Stability and safety in a modern car is greatly improved? comment on the
statement.
f. What are the periodic observations replacementxfgp?rts/?lllngs required over few
thousand kilometers running of an Automobile?. ,. 1
g. What IS the reason for emitting the white exhaust smoke during start of the vehicle? .3": (
How will you prevent this? , $211135"?
h. What IS the signi?cance of BS 3 an??igs 4 engines? 311"?
i. What 13 king pin offset? 1 g;
j. Compare Hotchkiss drive & t5$1e tube drive 1:1? 7
W SECTION B 1
2. Attempt any three of the W'ng: 3;? " ?t: .1 10 x 3= 30
(a) The air resmtancgag? rolling resistance of a car are given by Ra = 0. 01V2 and
R = 7.5 + 0 e resistance being expressed 1n N Q3151 speed 1n km/h. If the
transmission ef?eiency 1n top gear: 90%, calculate the engine B ..P required at the ..
vehicle speed of 130 km/h. Also ?nd the vehicle aecel?ration 1n m/s2 at the instant
when the gear is moving at 50 km/h 1n top gear.; g?ijyeh engine torque at 50 km/h ?
1 3 X engine torque at 130 km/h and for cal?ulation of force the vehicle can be
assumed to be equivalent to weight of 176i3N
(b) A car has pivot pins 114 cm apan length of each track arm is 15. 25 cm and the
track rod behind the axle IS 104 cm l?1?g Determine the wheel base for true rolling
of all wheels, when the mner wheel ?tub- axle Is at 550 to the centreline of the car.
(c) De?ne the following terms 2mg kte their signi?cance 1n respect of vehlcle stability:
(i) Pitching $9; 1_
(ii) Rolling
(iii) Bouncing
(iv) Yawing
(d) A petrol engine has a fuel consumption of 10 litre/h. The air-fuel ratio supplied
through the carburetor is 15, the choke has diameter of 20 mm. Determine the
diameter of the jet of carburetor if the top of the jet is 5 mm above the fuel level in
?oat chamber. The barometer reads 750 mm height of mercury and the temperature
is 320C. Neglecting compressibility of air. Assume Cda = 0.85 and Cdf= 700 kg/m3.
MANISH KUMAR JHA | 17-Dec-2018 13:32:20 I 117.55.242.131
(e) Write short notes on following:
(i) Preventive maintenance
(ii) Overhauling system
SECTION C
Attempt any one part of the following: 10 x 1 = 10
(a) Discuss following types of resistances encountered by a moving vehicle. Which
factors in?uence each of them and how can these resistances be minimized:
(i) Road resistance
(ii) Air or Wind resistance
(iii) Road gradient resistance
(b) A four-speed gear box is to be constructed for providing the ratios of 1.0, 1.46, 2.28
and 3.93 to 1 as nearly possible. The diametral pitch of each gear is 3.25 mm and
the smallest pinion is to have atleast 15 teeth. The centre distance between the main
and layout shaft is 78 mm. Determine the suitable number of teeth of the different
gears and the exact gear ratios thus available.
Attempt any one part of the following: 10 x 1 = 10
(a) Explain the working principal of two universal Jomts to obtain constant velocity.
(b) Explain the principle of Ackermann steering gear A vehicle using Ackermann
steering system has a wheel base 28Q cm front wheel track 122 cm, distance .
between king pin axes 108 cm. If the makrmum defection 0f the 1nner front Wheel
is 45?, calculate:
(i) The defection of the outer front wheel assuming true rolling motion of air
wheels 1n this position.
(ii) The turning radius of outer front wheel. .
Attempt any one part of thefellowmg ?iv 5? 10 x 1 = 10
1 ?if ? xii"
,1 1 {1%
(a) Derive the formula for reaction coming on tront and rear whee1 of a car when it is
descending a hill an?? brake IS applied to front wheel only, 111 terms of coef?cient of
friction, gradient Weight of vehicle and vehicle dlmenswns
(b) Differentiate clearly between the function of Spring and a shock absorber in
suspension system.Exp1ain the construction and workmg of a telescopic type of
shock absorber with the help of neat diagram
Attempt any one part of the following: _ ., 10 x l = 10
(a) Why is an ignition system needed 1nana?t?on10bile? What function does it serve?
Make comparison between T.C.I. and CWDI ignition system.
(b) What are fundamental requirements Of a fuel supply system in engine? Sketch and
explain the construction and aagorkmg of a fuel 1nj ector.
Attempt any one part of the following: 10 x 1 = 10
(a) What do you know ab?o11tbreak down maintenance? If a diesel vehicle stops on road
explain the possibility of stopping the vehicle 1n sequence.
(b) Classify the pollution control devices used 1n Automobiles? With the help of neat
sketch, describe working of any one.
MANISH KUMAR JHA I 17-Dec-2018 132321201117.55.242.131
This post was last modified on 29 January 2020