Download AKTU B-Tech 2nd Sem 2016-17 NME202 Engineering Mechanics Question Paper

Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU)) B-Tech 2nd Semester (Second Semester) 2016-17 NME202 Engineering Mechanics Question Paper

Printed Pagesz2 RollNo.I I I I I I I I I I I NME202
B.TECH.
THEORY EXAMINATION (SEM?II) 2016-17
ENGINEERING MECHANICS
T ime : 3 Hours Max. Marks : 100
Note .' Be precise in your answer. In case ofnumericalproblem assume data wherever not provided.
SECTION ? A
1. Explain the following: 10 x 2 = 20
(a) Explain coplanar concurrent forces.
(b) Explain Polygon law of forces.
(c) Explain coulomb?s law of friction.
(d) State and explain parallel axis theorem.
(e) Give the methods used to analyze the truss.
(f) Differentiate between perfect, imperfect and redundant truss.
(g) Where does the position of centre of gravity of cone and hemisphere lie?
(h) What is the difference between ductile and brittle material.
(i) Define coefficient of friction.
(j) Differentiate between shear force and bending moment.
SECTION ? B
2. Attempt any ?ve of the following questions: 5 x 10 = 50
(a) The sum of two concurrent forces P and Q is SOON and their resultant is 400N. If the
resultant is perpendicular to 'P', find P, Q and angle between P and Q.
(b) Two blocks A & B weighing 250N and 400N respectively are resting on an inclined
plane. They are connected by a string as shown in Fig. 1. The coefficient of friction
under the blocks and plane are ?AZ 0.25 and MB: 0.5,
(i) What should be the angle of 0 the plane at which the sliding of the blocks will
impend?
(ii) What will be the tension in the string?
m
(Fig. l)
(c) Two cylinders of diameters 100 mm and 50 mm, weighing 200 N and SON, respectively
are placed in a trough as shown in Fig. 2. Neglecting friction, find the reactions at
contact surfaces 1, 2, 3 and 4.
(d) Determine mass moment of inertia of the cone of radius ?r? and mass ?m? about its
centroidal axis.
(e) A ball is dropped from the top of a tower 30m high. At the same instant a second ball is
thrown upward from the ground with an initial velocity of 15m/sec. When and where
do they cross and with what relative velocity?
M_E_H
(f) Derive the bending equation: T _ E _ E

(g) The composite bar shown in Fig.3 is subjected to a tensile force of 30 kN and the
diameter of brass bar is 20mm, diameter of steel bar is 25mm. The extension observed
is 0.44mm. Find the Young?s modulus of brass, if Young?s modulus of steel is 2X105
N/mmz.
25mmo 20?
20mmo A
?- _ a
Stool Blass ?O P=30kN
+
SWmm?Dh?SOOmm?H Emu
Fig3 Fig4
(h) Two blocks shown in Fig-4 have weight A=20 N and B=10N and the coefficient of
friction between the block A and the horizontal plane is 0.25. If the system is released
from rest, and the B falls through a vertical distance 2m, what is the velocity attained
by the block B. Neglect the friction in the pulley and the extension of the string
SECTION ? C
Attempt any two of the following questions: 2 x 15 = 30
Draw the SFD and BMD of the overhanging beam loaded as shown in Fig-5
2D Ir." 1H} k"
25 k" .Fm
Fig 5
A ladder of length L rests against a wall, the angle of inclination being 45?. If the coefficient of
friction between the ladder and the ground and that between ground and the wall is 0.5 each,
what will be the maximum distance on ladder to which a man whose weight is 1.5 times the
weight of ladder may ascend before the ladder begins to slip?
The cross?section of a plain concrete culvert is as shown in Fig. 7. Determine the moment of
inertia of the shaded area about the horizontal centroidal axes. All the dimensions are in mm.
Iv-400?+?1000?+?4m-o|
_?_
Fig 7