Ql. A 100 N block A rests on a 150 N block which rests on a rough horizontal plane.The block A is tied with a weightless horizontal cord to a wall. A force P is applied to the block B at 45º to the horizontal as shown in the figure. If the coefficient of friction is 0·25 between the· blocks and 0·3 between block Band the floor, determine the tension Tin the cord and the value of the force· P so that block B is at the point of sliding.

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Find the maximum. flexural stress developed in a steel wire 2·00 mm in diameter, if it is coiled over a drum 0·5 m in radius (it is assumed that the limit of proportionality is not exceeded due to coiling). What is the bending moment to which the wire is subjected Take E 200 GPa.


if the ratio of Young's modulus to the modulus of rigidity is 2·5 for a certain material, find its Poisson's ratio and the ratio of Young's modulus to bulk modulus.

An aeroplane flying at 300 km/h turns towards the left and completes a quarter circle of 80 m radius. The .mass of the rotary engine and the propeller of the plane is 500 kg with a radius of gyration of 300 mm. The engine speed is 2000 r.p.m. clockwise when viewed from the nose end (front end). Determine the gyroscopic couple on the aircraft and state its effect whether the nose end is raised or depressed

Define the following terms for the governor
• Sensitiveness
• Stability
• Isochronous
• Hunting

Draw the controlling force vs. radius of rotation of balls for spring controlled governors ·for the above conditions.

A gear set consists of an 18-tooth pinion driving a 45-tooth gear. The module is 10 mm. The gears are cut using a pressure angle of 20º. In mounting the gears, the centre distance was incorrectly made 8 mm larger. Compute the new values of the pressure angle and pitch circle diameter, If the pinion transmits 20 kW and rotates at 950 r.p.m.,
determine the forces on the tooth for mounted gears.


Q2.(a) A beam of uniform section and length 2a) is simply supported over a span L with two equal overhanging lengths Compute the deflection at mid span due to a uniformly distributed load w/unit length when covering the length L between the supports and when covering only two overhanging lengths. EI is the flexural rigidity of the beam.

A cam operates a roller reciprocating follower with the following data:
Minimum radius of the cam= 24 mm
Lift= 30 mm
Roller diameter= 16 mm
The cam lifts the follower for 120º with SHM followed by a dwell period of 40º. Then the follower lowers down during 150º of the cam rotation with uniform acceleration followed by a dwell period

Draw the profile of the cam.

If the cam rotates at a uniform speed of 160 r.p.m., calculate the maximum velocity and acceleration of the follower during the descent period.

A rotating shaft shown in the figure below is supported in ball bearings at A and D and loaded by a non-rotating force of 6·8 kN. The shaft is made of 40 C8 steel (σy 360 N/mm2, σu 650 Endurance limit σe may be taken· as 55% of σu: The shaft is machined. The reliability is 90% (reliability factor Cr is 0·897). Static stress
concentration at BB may be taken as 1·5 and at CC 1·4. The notch sensitivity factor q may be taken as 0·95.

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Find out the critical section and factor of safety.





Q3.
Draw the shear force and bending moment diagram for the given simply supported beam with moment loads as shown in the figure. Show the magnitude of shear force and bending moments at the respective points of the beam, i.e., at D and E.
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Determine the maximum shear stress values for the given set of principal stresses. Draw the Mohr's stress circle for each case and show the maximum shear stress on it.
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Derive the expression for minimum number of teeth on a pinion for involute rack in order to avoid interference .

A pinion of 30 involute teeth and 4 mm module drives a rack. The pressure angle is 20º. The addendum of both, the pinion and the rack is the same. What is the permissible value of the addendum to avoid interference?

A pair of spur gears with pressure angle 20º consists of a 24-tooth pinion which rotates at 950 r.p.m. and transmits power to a 60-tooth gear. The module is 6 mm and face width is 60 mm.both the gears are made of 45 C8 steel Take surface endurance limit 1500 N/mm^2. Assuming overload factor as 1·8, dynamic factor as 2·5 and taking factor of safety of 2·5, determine

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Beam strength

Wear strength

The rated power, the gears can transmit.

2·1 x 105 N/mm^2


Q4. A steam turbine delivers 8200 kW of power at 1800 r.p.m. This power is received by a shaft coupled with the turbine. This shaft delivers this power to the other shaft through gear reduction unit at 90% efficiency. The other shaft rotates at 107 r.p.m. Determine the diameters of both
the solid shafts. Take allowable shear stress as 3·45 x 108 N/m^2. Further, if these shafts are replaced by hollow shafts with internal diameters half of the outer diameter, determine the internal and external diameters of both the shafts.

A 100 kg machine is symmetrically supported on four springs. The mass of the reciprocating parts is 2·5 kg which move through a vertical stroke of 100 mm with SHM.
Neglecting damping, determine the combined stiffness of the springs so that the force transmitted to the foundation is 1/20th of the impressed force. The machine crankshaft rotates at 850 r.p.m. If under actual working conditions, the damping reduces the amplitudes of successive vibrations by find

the force transmitted to the foundation at 850 r.p.m.,

the force transmitted to the foundation at resonance, and

the amplitude of the vibration at resonance.

A ball bearing operates on a work cycle consisting of three parts a radial load of 3500 N at 1440 r.p.m. for 30% of the cycle, a radial load of 6000 750 r.p.m. for 35% of the cycle and a radial load of 2500 N at 1440 r.p.m. for the remaining cycle. The expected life of the bearing is 10,000 hours. Calculate the dynamic load carrying capacity of the bearing.


Q5.
Explain briefly Nitriding, Cyaniding, Flame Hardening and Induction Hardening.

Classify gating designs in respect to pouring of molten metals into the mould cavity in the casting process. Give sketches of simple vertical gating, and
bottom gating design provisions.

M/s TV Assembler needs 10,000 tubes per annum. The cost of one procurement is RS 80·00. The holding cost per tube is RS 3·00 per annum. The rush purchase of tubes, if not in stock, amounts to equivalent shortage cost of RS 6·00 per tube per annum.
If the order is delivered instantaneously, determine how much he should order; at what interval and what will be the total cost of-inventory.


List out any six inherent characteristics of a hydraulic actuator.

Explain the working of a gear pump with the help of a schematic diagram. Also details other properties.

Determine the missing elements of the following frame representation, if the frame is attached to an object in space. Also show the orientation and position of the frame F with respect to OXYZshown.

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Q6.(a)
Explain uniform corrosion and pitting corrosion.

For a 79·65wt% Fe, 0·35 wt% an alloy is at a temperature just below the eutectoid. Determine the fraction of total ferrite and cementite phases, the fraction of the proeutectoid ferrite and pearlite, and the fraction of the eutectoid ferrite.

The following table shows the activities of a network along with their time estimates in days

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Draw the project network and find the probability of completion of the project in 40 days.

Describe with an illustrative sketch the "Ultrasonic Welding" process.
Explain the following control strategies

Proportional Control

Derivative Control

Integral Control

PID Control

Derive the forward kinematics equations for the given figure of two degrees of freedom planar robot. Assign the coordinate frames based on D-H representations, prepare
the D-H parameter table, prepare the individual transformation matrices and finally the composite transformation matrix depicting the F-K equations.

If the link lengths are a1 15 units and a2 10 units, determine the final position and orientation of tool point (e.e.) frame for θ1 45º and θ2 45º (measured in
counter-clockwise sense).

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Q7.(a)
Describe the stress strain behaviour and glass transition temperature for polymers.

Define the term hardenability and the factors affecting it. Also name various hardening methods.

For a deterministic inventory model assuming uniform rate of supply and fixed demand, illustrate the model graphically,(b)Derive the expression for optimum order quantity (c)derive the expression for the optimum time for ordering, and derive the expression for the cost of inventory.

Give a schematic diagram of a piezoelectric accelerometer for shock and vibration measurement and briefly explain how it works.

c.
Describe in brief the following forms of memory units
ROM,PROM,EPROM,EEPROM,RAM

Determine and compare the coordinates of a point
attached ·to a moving frame Fuvw which undergoes the following
two sets of successive transformation

Set A:l. First a rotation of 90º) about Z-axis.
2. Followed. by translation of 3 about the Y and Z axes respectively.
3. Finally a rotation of 90º) about Y-axis.

Set B:l. First a rotation of 90º) about W-axis.
2. Followed by translation of about the V and W axes respectively.
3. Finally a rotation of 90º) about V-axis.

Q8.
How is the heat for electron beam welding obtained With the help of a diagram, discuss the working of this method of welding.

Describe with neat sketch the method of cold drawing of a wire or a bar.

The dimensions of the mating parts according to the hole system are given below

Hole 30·0 mm Shaft 29·98 mm
30·05 mm 29·94 mm

Find the hole tolerance, shaft tolerance and allowance.

Illustrate and describe through a linking flow diagram, the elements of a CIM system for integrating CAD/CAM including latest communication technology to all the operational functions and information processing in manufacturing.

c.
Develop Forward Kinematics model for the given three degrees of freedom RPY wrist figure. Assign the frames, develop D-H parameters table, generate individual transformation matrices and overall transformation matrix. Assume a3 d3 0. Determine the orientation of the last frame with reference to the frame, if θ1 0 and θ2 θ3 90º.
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Determine the three joint variables for a given end effector orientation matrix TE for the RPY wrist in the figure above.

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