Solved University Question Papers December-2017

Solved University Question Papers

December-2017

Engineering Mechanics

Semester - II (Mechanical / Civil) Regulation 2013

[Time: Three Hours] [Maximum Marks: 100]

AU Solved Paper (50655)

Answer ALL Questions

PART A - (10 x 2 = 20 Marks)

Q.1

State the polygon law of forces. 

[Refer Two Marks Q.25 of chapter - 1] 

Q.2

State the principle of transmissibility. 

[Refer Two Marks Q.9 of chapter - 1] 

Q.3

State and prove Varignon's theorem. 

[Refer Two Marks Q.2 of chapter - 3] 

Q.4

Sketch the free body diagram for the cylinder B shown in Fig. 1. 

[Refer Two Marks Q.16 of chapter - 2]

Q.5

By using Pappus theorem, determine the volume of sphere having radius r. 

[Refer Two Marks Q.7 of chapter - 5]

Q.6

State the relationship between the second moment of area and mass moment of inertia for a uniform plate. 

[Refer Two Marks Q.6 of chapter - 7]

Q.7

Equation of motion of a body is s 5t3 + 4t3 +3t +2. Find velocity and acceleration. 

[Refer Two Marks Q.22 of chapter - 9]

Q.8

Define instantaneous velocity. 

[Refer Two Marks Q.23 of chapter - 9]

Q.9

Define rolling resistance. 

[Refer Two Marks Q.14 of chapter - 8]

Q.10

Define coefficient of friction. 

[Refer Two Marks Q.2 of chapter 8] 

PART B - (5 x 16 80 Marks)

Q.11 

a) Three links PQ, QR and RS connected as shown in Fig. 2 support loads W and 50 N. Find the weight W and the force in each link if the system remains in equilibrium. 

[Refer example 4.6.43]

OR

b) Two identical rollers each of weight 2.5 kN rest in between an inclined wall and a vertical wall as shown in Fig. 3. Determine the reactions at the points of contact P, Q and R. Assume the wall surfaces to be smooth. 

[Refer example 2.11.8]

Q.12 

a) Reduce the given system of forces acting on the beam AB in Fig. 4. to (i) An equivalent force couple system at A (ii) An equivalent force couple system at B. 

[Refer example 3.10.20]

OR

b) Find the pin reaction of A and the roller reaction at B. For the beam shown in Fig. 5. 

[Refer example 4.6.37]

Q.13 

a) Determine the second moment of area of a triangle about its base and along the axis passing through the centre of gravity. 

[Refer section 6.5.2]

OR

b) Find the mass moment of inertial of the rectangular block shown in Fig. 6, about the vertical y axis. A cuboid of 20 mm × 20mm × 20mm has been removed from the rectangular block as shown in Fig. 6. The mass density of the material of the block is 7850 kg/m3. 

[Refer example 7.5.1]

Q.14 

a) A body moves along a straight-line so that its displacement from a fixed point on the line is given by s = 4t3 −6t2 + 20. Find the displacement velocity and acceleration at the end of 3 seconds. 

[Refer example 9.1.5]

OR

b) A particle starting from rest, moves in a straight line and its acceleration is given by a = 50 - 36t2 m/s2 where t is in sec. Determine the velocity of the particle when it has traveled 52 m. 

[Refer example 9.1.17]

Q.15 

a) Two block of mass 20 kg and 40 kg are connected by a rope passing over a frictionless pulley as shown in Fig. 7. Assuming the coefficient of friction as 0.3 for all contact surfaces. Find the tension in the string and the acceleration of the system. Also compute the velocity of the system after 4 seconds starting from rest. 

[Refer example 9.3.4]

OR

b) A body weighing 196.2 N slides up a 30° inclined plane under the action of an applied force 300 N parallel to be plane. The coefficient of friction is 0.2 the body move from rest. Determine at the end of 4 sceconds, the acceleration, distance traveled, velocity, kinetic energy, work done, momentum and impulse applied on the body. 

[Refer example 9.3.20]

The free body diagram is drawn as shown in Fig. 8.