The number of degrees of freedom of a planar linkage with 8 links and 9 simple revolute joints is

The number of inversions for a slider crank mechanism is

Balancing of a rigid rotor can be achieved by appropriately placing balancing weights in

The Klein's method of construction for reciprocating engine mechanism

In reciprocating engines, primary forces

The ratio of tension on the tight side to that on the slack side in a flat belt drive is

In a $6 imes 20$ wire rope, No. 6 indicates the

In case of a multiple disc clutch, if $n_1$ is the number of discs on the driving shaft and $n_2$ is the number of discs on the driven shaft, then what is the number of pairs of contact surfaces?

The minimum number of teeth on the pinion to operate without interference in standard full-height involute teeth gear mechanism with $20^\circ$ pressure angle is

Which type of gear is used for shaft axes having an offset?

With the help of neat sketch, explain the following: Link, Kinematic pair, Kinematic chain, Mechanism and Machine.

Sketch and explain the working principle of Whitworth quick return motion mechanism.

Sketch and explain elliptical trammels and Scotch yoke mechanism of a double-slider crank chain.

In a crank and slotted lever quick return motion mechanism, the distance between the fixed centres is 240 mm and the length of the driving crank is 120 mm. Find the inclination of the slotted bar with the vertical in the extreme position and the time ratio of cutting stroke to the return stroke. If the length of the slotted bar is 450 mm, find the length of the stroke if the line of stroke passes through the extreme positions of the free end of the lever.

With the help of example, explain instantaneous centre method for finding velocity of a point on a link.

A mechanism is shown in Fig. 1, with following dimensions: $O_1A = 60$ mm; $AB = 180$ mm; $O_2B = 100$ mm; $O_2C = 180$ mm and $CD = 270$ mm. The crank $O_1A$ rotates clockwise at a uniform speed of 120 r.p.m. The block $D$ moves in vertical guides. Find, by instantaneous centre method, the velocity of $D$ and the angular velocity of $CD$.

Explain how the velocities of a slider and the connecting rod are obtained in a slider crank mechanism.

In a slider crank mechanism as shown in Fig. 2, the crank is 200 mm long and rotates at 40 rad/sec in a CCW direction. The length of the connecting rod is 800 mm. When the crank turns through $60^\circ$ from inner-dead centre, determine— (i) the velocity of the slider; (ii) the velocity of point $E$ located at a distance of 200 mm on the connecting rod extended; (iii) the position and velocity of point $F$ on the connecting rod having the least absolute velocity; (iv) the angular velocity of connecting rod; (v) the velocity of rubbing of pins of crank shaft, crank and cross head having pins diameters 80 mm, 60 mm and 100 mm respectively.

Describe with a neat sketch the working of a cone clutch.

A conical friction clutch is used to transmit 90 kW at 1500 r.p.m. The semi-cone angle is $20^\circ$ and the coefficient of friction is 0.2. If the mean diameter of the bearing surface is 375 mm and the intensity of normal pressure is not to exceed $0.25\text{ N/mm}^2$, find the dimensions of the conical bearing surface and the axial load required.

Explain the method to determine velocity ratio of a compound belt drive.

A leather belt is required to transmit 7.5 kW from a pulley 1.2 m in diameter, running at 250 r.p.m. The angle embraced is $165^\circ$ and the coefficient of friction between the belt and the pulley is 0.3. If the safe working stress for the leather belt is 1.5 MPa, density of leather $1\text{ mg/m}^3$ and thickness of belt 10 mm, determine the width of the belt taking centrifugal tension into account.

Discuss the phenomena of interference in involute gear.

A pair of involute spur gears with $16^\circ$ pressure angle and pitch of module 6 mm is in mesh. The number of teeth on pinion is 16 and its rotational speed is 240 r.p.m. When the gear ratio is 1.75, find in order that the interference is just avoided— (i) the addenda on pinion and gear wheel; (ii) the length of path of contact; (iii) the maximum velocity of sliding of teeth on either side of the pitch point.

When a cylinder is located in a vee-block, then number of degrees of freedom which are arrested is

A planar mechanism has $8$ links and $10$ rotary joints. The number of degrees of freedom of the mechanism, using Grubler's criterion is

The lengths of the links of a 4$-bar linkage with revolute pairs only are $p, q, r and $s$ units. Given that $p < q < r < s$. Which of these links should be the fixed one, for obtaining a 'double crank' mechanism?

The sense of Coriolis component $2\omega V$ is the same as that of the relative velocity vector $V$ rotated

If a two-mass system is dynamically equivalent to a rigid body, then the system will not satisfy the condition that the

Two rotors are mounted on a shaft. If the unbalanced force due to one rotor is equal in magnitude to the unbalanced force due to the other rotor, but positioned exactly $180^\circ$ units apart, then the system will be balanced

In spur gears, the circle on which the involute is generated is called the

If the pressure angle of the rack is $20^\circ$, then force acting along the line of action between the rack and the gear teeth is

Which one of the following is not a friction clutch?

Total slip will occur in a belt drive when

What are kinematic pairs? With the help of example, classify kinematic pairs according to nature of relative motion between pairing elements.

Sketch and explain the working principle of third inversions of a single slider crank chain mechanism.

Sketch and explain any two inversions of a double slider crank chain.

The Whitworth quick return motion mechanism has the driving crank $160\text{ mm}$ long. The distance between fixed centres is $110\text{ mm}$. The line of stroke of the ram passed through the centre of rotation of the slotted lever whose free end is connected to the ram by a connecting link. Find the ratio of time of cutting to time of return.

State and prove the 'Aronhold-Kennedy's Theorem' of three instantaneous centers.

In a four-bar chain $ABCD$, $AD$ is fixed and is $165\text{ mm}$ long. The crank $AB$ is $45\text{ mm}$ long and rotates at $120\text{ r.p.m.}$ clockwise, while the link $CD = 80\text{ mm}$ oscillates about $D$. $BC$ and $AD$ are of equal lengths. Find the angular velocity of link $CD$ when angle $BAD = 65^\circ$.

With the help of a neat sketch, explain acceleration diagram of a slider crank mechanism.

In a four-bar chain $ABCD$, link $AD$ is fixed and crank $AB$ rotates at $10\text{ radians per second}$ clockwise. Lengths of the links are AB = 60\text{ mm}$; $BC = CD = 70\text{ mm}$; $DA = 120\text{ mm}. When angle $DAB = 60^\circ$ and both B and C lie on the same side of $AD$, find—

Describe with a neat sketch the working of a single-plate friction clutch.

A multiplate clutch has three pairs of contact surfaces. The outer and inner radii of the contact surfaces are $100\text{ mm}$ and $50\text{ mm}$ respectively. The maximum axial spring force is limited to $1\text{ kN}$. If the coefficient of friction is $0.35$ and assuming uniform wear, find the power transmitted by the clutch at $1500\text{ r.p.m.}$

Explain the phenomena of 'slip' and 'creep' in a belt drive.

Determine the width of a $9.75\text{ mm}$ thick leather belt required to transmit $15\text{ kW}$ from a motor running at $900\text{ r.p.m.}$ The diameter of the driving pulley of the motor is $300\text{ mm}$. The driving pulley runs at $300\text{ r.p.m.}$ and the distance between the centres of two pulleys is $3\text{ metres}$. The density of the leather is $1000\text{ kg/m}^3$. The maximum allowable stress in the leather is $2.5\text{ MPa}$. The coefficient of friction between the leather and pulley is $0.3$. Assume open belt drive and neglect the sag and slip of the belt.

Define the following terms related to gear:

The following data relates to a pair of $20^\circ$ involute gears in mesh: Module $= 6\text{ mm}$ Number of teeth on pinion $= 17$ Number of teeth on gear $= 49$ Addenda on pinion and gear wheel $= 1\text{ module}$ Calculate—

When a cylinder is located in a vee-block, then number of degrees of freedom which are arrested is

A planar mechanism has 8 links and 10 rotary joints. The number of degrees of freedom of the mechanism, using Grubler's criterion is

The lengths of the links of a 4-bar linkage with revolute pairs only are $p$, $q$, $r$ and $s$ units. Given that $p < q < r < s$. Which of these links should be the fixed one, for obtaining a 'double crank' mechanism?

The sense of Coriolis component $2\omega V$ is the same as that of the relative velocity vector $V$ rotated

If a two-mass system is dynamically equivalent to a rigid body, then the system will not satisfy the condition that the

Two rotors are mounted on a shaft. If the unbalanced force due to one rotor is equal in magnitude to the unbalanced force due to the other rotor, but positioned exactly $180^\circ$ apart, then the system will be balanced

In spur gears, the circle on which the involute is generated is called the

If the pressure angle of the rack is $20^\circ$, then force acting along the line of action between the rack and the gear teeth is

Which one of the following is not a friction clutch?

Total slip will occur in a belt drive when

What are kinematic pairs? With the help of example, classify kinematic pairs according to nature of relative motion between pairing elements.

Sketch and explain the working principle of third inversions of a single slider crank chain mechanism.

Sketch and explain any two inversions of a double slider crank chain.

The Whitworth quick return motion mechanism has the driving crank 160 mm long. The distance between fixed centres is 110 mm. The line of stroke of the ram passed through the centre of rotation of the slotted lever whose free end is connected to the ram by a connecting link. Find the ratio of time of cutting to time of return.

State and prove the 'Aronhold-Kennedy's Theorem' of three instantaneous centers.

In a four-bar chain $ABCD$, $AD$ is fixed and is 165 mm long. The crank $AB$ is 45 mm long and rotates at 120 r.p.m. clockwise, while the link $CD = 80$ mm oscillates about $D$. $BC$ and $AD$ are of equal lengths. Find the angular velocity of link $CD$ when angle $BAD = 60^\circ$.

With the help of a neat sketch, explain acceleration diagram of a slider crank mechanism.

In a four-bar chain $ABCD$, link $AD$ is fixed and crank $AB$ rotates at 10 radians per second clockwise. Lengths of the links are $AB = 60$ mm; $BC = CD = 70$ mm; $DA = 120$ mm. When angle $DAB = 60^\circ$ and both $B$ and $C$ lie on the same side of $AD$, find— (i) angular velocities (magnitude and direction) of $BC$ and $CD$; (ii) angular acceleration of $BC$ and $CD$.

Describe with a neat sketch the working of a single-plate friction clutch.

A multiplate clutch has three pairs of contact surfaces. The outer and inner radii of the contact surfaces are 100 mm and 50 mm respectively. The maximum axial spring force is limited to 1 kN. If the coefficient of friction is 0.35 and assuming uniform wear, find the power transmitted by the clutch at 1500 r.p.m.

Explain the phenomena of 'slip' and 'creep' in a belt drive.

Determine the width of a 9.75 mm thick leather belt required to transmit 15 kW from a motor running at 900 r.p.m. The diameter of the driving pulley of the motor is 300 mm. The driving pulley runs at 300 r.p.m and the distance between the centres of two pulleys is 3 metres. The density of the leather is $1000\text{ kg/m}^3$. The maximum allowable stress in the leather is 2.5 MPa. The coefficient of friction between the leather and pulley is 0.3. Assume open belt drive and neglect the sag and slip of the belt.

Define the following terms related to gear: (i) Pitch circle diameter (ii) Angle of obliquity (iii) Circular pitch (iv) Module

The following data relates to a pair of $20^\circ$ involute gears in mesh: Module = 6 mm Number of teeth on pinion = 17 Number of teeth on gear = 49 Addenda on pinion and gear wheel = 1 module Calculate— (i) the number of pairs of teeth in contact; (ii) the angle turned through by the pinion and the gear wheel when one pair of teeth in contact; (iii) the ratio of sliding to rolling motion when the tip of a tooth on the larger wheel (1) is just making contact, (2) is just leaving contact with its mating tooth and (3) is at the pitch point.