# Mechanics and Machines

A machine (or mechanical device) is a mechanical structure that uses power to apply forces and control movement to perform an intended action. Machines can be driven by animals and people, by natural forces such as wind and water, and by chemical, thermal, or electrical power, and include a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement. They can also include computers and sensors that monitor performance and plan movement, often called mechanical system.

Torsional pendulum is used to determine mass moment of inertia of
Which of the following conditions should be satisfied for a two point mass statistically equivalent system?

Calculate the thrust in connecting rod, if piston effort is 200 kN and crank makes an angle of 45ofrom TDC. Assume obliquity ratio = 3.5
The coefficient of friction is high in multi disk plate clutch.
Scotch yoke mechanism is the inversion of
Maximum efficiency of spiral gears is given as
Which type of gears have point contact between two mating gears?
Which of the following statements is/are true?
Which motion of follower is best for high speed cams?
Which of the following conditions can be used to minimize undercutting in cam and follower mechanism?
Why are graphical errors caused during function generation?
Which among the following is not a type of error found in function generation?
The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as
A point B on a rigid link AB moves with respect to A with angular velocity ωrad/s. The total acceleration of B with respect to A will be equal to
Secondary force in reciprocating engine mechanism is caused due to _______
In a locomotive, the ratio of the connecting rod length to the crank radius is kept very large in order to
Multi-cylinder engines are desirable because
When a body is subjected to transverse vibrations, the stress induced in a body will be
The factor which affects the critical speed of a shaft is
If number of contacting surfaces are 5, then number of disks required in multi disk clutch are?
The two parallel and coplanar shafts are connected by gears having teeth parallel to the axis of the shaft. This arrangement is called
The type of gears used to connect two non-parallel non-intersecting shafts are
A four-bar chain has
The mechanism in a shaping machine is
The force of friction between belt and V grooved pulley is high.
There is problem of bending stress in the V belt drive.
Among spur gear and helical gear, which has smooth engagement and thus lesser noise?
There is same type of tooth meshing in helical and spur gear.
Among the normal module and transverse module, which one has greater value?
Below is a representation of a helical gear. Blue lines in the figure signify?

The direction of tangential component for a driving gear is same to the direction of rotation.
If tangential component of force on tooth is 200N and helix angle is 25⁰, calculate the axial component of the force.
If compressive yield stress and tensile yield stress are equivalent, then region of safety from maximum principal stress theory is of which shape?
How many classes of levers are there?
V belts result in smooth and quite operation even at high speeds.
Which of the following conditions should be satisfied for complete balancing of multi-cylinder inline engines?
Which of the following statements is/are true for V-belts?
A pair of parallel helical gears consist of 15 teeth pinion meshing with a 40 teeth gear. The helix angle is 22⁰ and normal pressure angle 19⁰. The normal module is taken as 4mm. Calculate the pitch circle diameter of pinion.
Cycloidal teeth consist of
Secondary force in reciprocating engine mechanism is caused due to _______.
Solid shafts are used in epicyclic gearboxes.
The moment of forces about the CG is ?
Solid shaft is costlier than hollow shaft of same weight.
Velocity ratio is the ratio angular velocity of driving gear to that of driven gear.
Flexible shafts have ___ rigidity in torsion making them flexible.
Calculate equivalent stiffness of the spring for the system shown below, which has spring stiffness of 3000 N/m
The stiffness of solid shaft is more than the stiffness of hollow shaft with same weight.
The magnitude of linear velocity of a point B on a link AB relative to point A is
The relative acceleration of two points which are at variable distance apart on a moving link can be determined by using the
Scotch yoke mechanism is used to generate
If driving gear rotates CW, driven gear will rotate?
Is it possible to use worm gears in cranes for lifting purpose?
A pair of parallel helical gears consist of 15 teeth pinion meshing with a 40 teeth gear. The helix angle is 22⁰ and normal pressure angle 19⁰. The normal module is taken as 4mm. Calculate the axial pitch.
During transverse vibrations, shaft is subjected to which type of stresses?
V belts have v shaped cross section
The efficiency of flat belt drive is 35%. If all the parameters are same and flat belt is replaced by V belt, than the efficiency of V belt will be?
Which type of vibrations are also known as transient vibrations?
The jaw clutches show great amount of slip.
In positive contact clutches, power transmission is achieved by means of friction.
Which of the following are inversions of a double slider crank chain?
1. Whitworth return motion
2. Scotch Yoke
3. Oldham’s Coupling
4. Rotary engine
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