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UNIT-1------2 marks (PART A)

1. Distinguish the following system of forces with a suitable sketch. a) Coplanar b)

Collinear

2.State parallelogram law and triangle law of forces.

3. Define principle of transmissibility. Explain with a neat sketch.

4. Two forces of magnitude 50 KN and 80 KN are acting on a particle, such that the

angle between the two is 135. If both the force are acting away from the particle,

calculate the resultant and find its direction.

5. List the different types of beams. Indicate them with neat sketch.

6. Two forces of 60 kN and 40 kN separated by a distance of 2 m are respectively

acting towards north and south. Find the resultant in magnitude and direction.

7. Find the magnitude of the two forces such that if they act at right angles, their

resultant is 10 N. But if they act at 60 their resulta

8. nt is 13 N.

9. What is a couple? what is a moment of a couple? .

10. List the different types of loads acting on the beam..

11. Two concurrent forces of 50 N each have their resultant also of 50 N magnitude.

Find the angle between these two forces.

UNIT 2------2 marks (PART A)1. Define friction and classify its types.

2. Define Limiting friction.

3. Define coefficient of static friction.

4. State coulombs laws of dry friction.

5. Define rolling resistance.

6. State the laws of friction

7. Define i) angle of repose

8. Define cone of friction.

9. Define Co-efficient of friction and angle of friction

10. Derive the relationship between coefficient of friction and angle of friction

UNIT 3------2 marks (PART A)1. Define center of gravity

2. Define centroid of a plane figure

3. Define axis of symmetry

4. Write the formula used to locate centroid of composite areas\

5. Distinguish between centroid & center of gravity

6. What is total weight of body

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7. With neat sketch show location of centroid of quarter circle and sector of circle

8. What is composite area or composite plane figure

9. Calulate the center of gravity of T-section 100mm x 150 mm x 50 mm from its

bottom

10.With neat sketch show location of centroid of right angled triangle and

symmetrical triangle

UNIT 4------2 marks (PART A)1. State parallel axis theorem

2. State perpendicular axis theorem

3. Find the polar moment of inertia of a hollow circular section of external diameter D andinternal diameter d.

4. Define principal axes and principal moment of inertia

5. Locate the centroid and calculate the moment of inertia about centroidal axes of a

semicircular lamina of radius 2m.

6. Define polar moment of inertia.

7. Explain concept of radius of gyration

8. Explain why Moment of inertia is called Second moment of area

9. What is moment of inertia of quadrant of a circle. Indicate with a neat sketch.

10. What is moment of inertia of sector of a circle. Indicate with a neat sketch.

UNIT 5------2 marks (PART A)

1. Explain the principle of virtual work.

2. State the principle of virtual work, and explain how it can be used for solving problems instatics.

3. Explain the application of the principle of virtual work in case of lifting machines.

4. How will you apply the principle of virtual work in finding out the forces in a framed

structure?

5. List the different type of lifting machines

6. A drum weighing 60 N and holding 420N of water is to be raised from a well by meansof wheel and axle. The axle is 100 mm diameter and the wheel is 500 mm diameter. If a

force of 120 N has to be applied to the wheel, find (i) mechanical advantage

7. The larger and smaller diameters of a differential wheel and axle are 80 mm and 70 mmrespectively. The effort is applied to the wheel of diameter 250 mm. What is the velocity

ratio?8. With a differential wheel and axle, an effort of 6 N raised a load of 60 N. If the efficiency

at this load is 80%, find the velocity ratio of the machine.

9. Describe the working of a Westons differential pulley block.

10. Distinguish clearly between a simple wheel and axle and a differential wheel and axle.

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UNIT 1------5 marks (PART B)

1. The forces shown in the figure below are in equilibrium. Determine the forces F1 and

F2

2. A force P is applied at O to the string AOB as shown in fig. If the tension in each part of

string is 50 N, find the direction an magnitude of force P for equilibrium conditions.

3. Two identical rollers each of weight 50N are supported by an inclined plane and avertical wall as shown in fig. Find the reactions at the points of supports A, B, and C.

4. A precast concrete post weighing 50 Kg and of length 6m shown in fig. is raised for

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placing it in position by pulling the rope attached to it. Determine the tension in the rope

and the reaction at A.

5. Two forces of 100 N and 80 N, having an included angle of 135 o , are acting at a point. Find

magnitude and direction of their resultant when both are pulled.

6. Two forces FA = 6 N ( Horizontal) and FB = 8 N (Inclined) act on particle and their lines ofactions are inclined to each other at an angle of 70 , find resultant

The force of 100 N acts at point A. Draw the free-body diagram of point A and calculate the

force developed in cable AC.

7. Calculate the resultant moment about point O.

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8. Calculate the resultant moment about point O.

9. Replace the three forces acting on the bent pipe by a single equivalent force R. specify the

distance x from point O to the point on the x-axis through which the line of action of R

passes.

10. On a sheet of paper draw the free-body diagram of member AB then find out the support

reactions

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UNIT 2------2 marks (PART A)

1. Blocks A and B of weight 200N and 100N respectively, rest on a 30 inclined planeand areattached to the post which is held perpendicular to the plane by force P,

parallel to the plane, as shown in fig. Assume that all surfaces are smooth and that

the cords are parallel to the plane. Determine the value of P. Also find the Normal

reaction of Blocks A and B.

2. Two Blocks A and B of weight 100 N and 200 N respectively are initially at rest on a

30inclined plane as shown in figure. The distance between the blocks is 6 m. The

co efficient of friction between the block A and the plane is 0.25 and that between

the block B and the plane is 0.15. If they are released at the same time, in what time

the upper block (B) reaches the Block (A).

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3. Block (2) rests on block (1) and is attached by a horizontal rope AB to the wall as

shown in fig. What force P is necessary to cause motion of block (1) to impend? The

co-efficient of friction between the blocks is and between the floor and block (1) is

1/3. Mass of blocks(1)and(2) are 14kg and 9 kg respectively

4. Block A weighing 1000 N rests on a rough inclined plane whose inclination to the

horizontal is 45. It is connected to another block B, weighing 3000 N rests on a

rough horizontal plane by a weightless rigid bar inclined at an angle of 30 to the

horizontal as shown in fig. Find the horizontal force required to be applied to the

block B just to move the block A in upward direction. Assume angle of friction as 15

at all surfaces where there is sliding

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5. An effort of 200 N is required just to move a certain body up an inclined plane of

angle 15, the force is acting parallel to the plane. If the angle of inclination of the

plane is made 20, the effort required being again parallel to the plane, is found to be

230 N. Find the weight ofthe body and coefficient of friction

.6. Find the force P inclined at an angle of 32 to the inclined plane making an angle

of 25 degree with the horizontal plane to slide a block weighing 125 KN (i) up the

inclined plane (ii) Down the inclined plane, when P = 0.5.

7. In a screw jack, the pitch of the square threaded screw is 5.5 mm and means

diameter is 70 mm. The force exerted in turning the screw is applied at the end of

lever 210 mm long measured from the axis of the screw. If the co-efficient of friction

of the screw jack is 0.07. Calculate the force required at the end of the lever to (i)

raise a weight of 30 KN (ii) lower the same weight.

8. A 7m long ladder rests against a vertical wall, with which it makes an angle of 45

and on a floor. If a man whose weight is one half that of the ladder climbs it, at

what distance along the ladder will he be, when the ladder is about to slip? Take

coefficient of friction between the ladder and the wall is 1/3 and that between the

ladder and the floor is

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9. A weight 500 N just starts moving down a rough inclined plane supported by a force of200N acting parallel to the plane and it is at rbe point of moving up the : plane when

pulled by a force of 300 N parallel to the plane. Find the inclination of , the plane and

the coefficient of friction between the inclined plane and the weight.

10.BlockA weighing 1000N rests over blockB weighs 2000 N as shown in Fig. BlockA

is tiedwith a horizontal string. If the coefficient of friction between A and B is 1/4 and

betweenB and the floor 'is 113, what should be the value ofPto move the bJockB if

(a)P is horizontal?

(b) Pacts 300 upwards to horizontal?

UNIT 3------2 marks (PART A)

1. Derive the centroid of a right angled triangle

2. Derive the centroid of a semi circle

3. Derive the centroid of a sector of a circle

4. Find the centroid of the unequal angle 200 150 12 mm, shown in Fig

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5. Locate the centroid of the I-section shown in Fig.

6. Find the moment of inertia of the section shown in the figure about its horizontal

centroidal axis

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7. Calculate the mass moment of inertial of the plate shown in figure with respect

to the axisAB. Thickness of the plate is 5 mm and density of the material is 6500

Kg/m3.

8. Derive expression form mass moment of inertia of prism along three axes.

9. Calculate the mass moment of inertia about the axis AB the junction of cone and

cylinder and also ZZ axis for the given figure.

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10. Determine moment of inertia for the figure shown about base AB

UNIT 5------2 marks (PART A)

1. In a simple wheel and axle, radii of effort wheel and axle is 240 mm and 40 mm

respectively. Find the efficiency of the machine, if a load of 600 N can be lifted by an

effort of 120 N

2. In a simple wheel and axle, the diameter of the wheel is 150 mm and that of the axle

is 30 mm. If efficiency of the machine is 60%, determine the effort required to lift a

load of 500 N.

3. A simple wheel and axle has wheel and axle of diameters of 300 mm and 30 mm

respectively. What is the efficiency of the machine, if it can lift a load of 900 N by

an effort of 100 N.

4. State and prove principle of virtual work.

5. A simply supported beam AB of span 5 metres is carrying a point load of 2 kN at a

distance 2 metres from A. Determine the beam reactions, by using the principle of

the virtual work.

6. A simply supported beam AB of span 5 m is loaded as shown in Fig

7. 7.A uniform ladder of weight 250 N rests against a smooth vertical wall and arough horizontal floor making an angle of 45 with the horizontal. Find the force of

friction at the floor using the method of virtual work.

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8. A uniform ladder, 5 metres long and weighing 200 N, rests on a smooth

floor at A and against a smooth wall at B as shown in Fig

9. A hexagonal frame is made up of six bars of equal length and cross section as

shown in Fig. The bar ED is fixed in a horizontal position. A rod GH is fixed at the

mid-points of the bars ED and AB. Using the principle of virtual work, find the tension

in the rod GH due to the weight of the bars.

10.A square pin-jointed frame ABCD with 500 mm side is subjected to a force of 100 N

at D and 50 N at C as shown in Fig.. All the pins are smooth and the bar weights areneglected.

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