A flywheel is used to store rotational energy. It helps in maintaining a constant speed by absorbing fluctuations in the energy supplied by the engine or other power sources. This function reduces the variation in the speed of the machine, improving overall performance.
Which of the following is the primary function of a governor?
A Regulate speed
B Store energy
C Convert motion
D Transmit power
A governor is a device used to regulate the speed of an engine by adjusting the fuel supply based on the engine’s speed. This is done to ensure the engine runs at a constant speed, compensating for load changes.
What does the slider‐crank mechanism primarily convert?
A Linear to angular motion
B Angular to linear motion
C Translatory to reciprocatory motion
D Rotary to oscillatory motion
The slider‐crank mechanism is designed to convert rotary motion into reciprocating linear motion. This is commonly used in engines where the rotation of the crankshaft produces linear motion in the piston.
What is the main purpose of gear trains in mechanical systems?
A Convert motion
B Increase power
C Increase torque
D Change speed
Gear trains are used to change the speed of rotation or direction of motion in mechanical systems. They do this by varying the gear ratio, which affects both the speed and torque output of the system.
What does the term “mechanical advantage” refer to?
A Ratio of torque to input
B Ratio of speed to output
C Ratio of output to input force
D Ratio of load to input
Mechanical advantage is the factor by which a machine multiplies the input force to produce a greater output force. It helps in understanding how efficiently a machine amplifies force, making tasks easier.
What does dynamic balancing of a rotating machine ensure?
A No vibration
B Increased power output
C Consistent speed
D Increased torque
Dynamic balancing ensures that the rotating parts of a machine have a uniform mass distribution. This minimizes vibrations during rotation, preventing wear and tear, and improving the longevity and performance of the machine.
What is the purpose of a cam mechanism?
A Provide a fixed movement
B Control linear motion
C Convert power
D Control rotational motion
A cam mechanism is used to convert rotary motion into a specific, controlled form of linear motion. It is commonly used in internal combustion engines to operate the intake and exhaust valves in a timed sequence.
In a gear system, what does the term “gear ratio” represent?
A Ratio of input to output torque
B Ratio of rotational speeds
C Ratio of teeth numbers
D Ratio of angular velocities
The gear ratio is the ratio of the number of teeth on two meshing gears. It determines how the rotational speeds of the gears are related and is crucial for calculating torque and speed in a system.
What is the main function of a belt drive in mechanical systems?
A Convert motion
B Transmit power
C Reduce vibrations
D Control speed
Belt drives are used to transmit mechanical power between pulleys or wheels, which are often connected by flexible belts. This setup is widely used for transmitting power in machinery, especially when the components need to be placed at a distance from each other.
In the context of mechanical vibrations, what does “resonance” refer to?
A Decreased amplitude
B Increased energy transfer
C Increased amplitude
D Decreased vibration frequency
Resonance occurs when a system vibrates at its natural frequency, leading to a significant increase in amplitude. This can cause excessive oscillations, which might damage the system if not properly managed.
Which of the following describes a four‐bar linkage mechanism?
A Four interconnected links
B Two moving links
C Four rotating links
D Two fixed links
A four‐bar linkage consists of four rigid links connected by four rotating pairs. This mechanism is widely used in applications such as robotic arms and various machines for producing specific types of motion.
What is angular velocity?
A Rate of change of displacement
B Rate of change of position
C Rate of change of velocity
D Rate of change of angle
Angular velocity refers to the rate at which an object rotates around a specific axis. It is measured in radians per second and describes how fast the angle changes with time during rotational motion.
What does the term “kinematic chain” refer to?
A A closed loop of rigid bodies
B A rotating mechanism
C A system of interconnected links
D A set of gears linked together
A kinematic chain is a series of links connected by joints that allow relative motion. It forms the basis of most mechanical mechanisms and is used to analyze motion and forces in machines.
What is the role of a chain drive in mechanical systems?
A Transmit torque
B Change speed
C Control vibrations
D Provide linear motion
A chain drive is used to transmit torque between two or more shafts in a machine, often where gears cannot be used. It is common in bicycles, motorcycles, and conveyor systems due to its efficiency and strength.
What is meant by “torque analysis” in machine dynamics?
A Studying rotational acceleration
B Analyzing forces in a rotating system
C Measuring resistance to motion
D Determining power loss
Torque analysis involves examining the rotational forces acting on a system, including how torque is transferred and distributed. It helps in understanding the mechanical behavior of rotating machines and ensuring they operate efficiently without failure.