Interview Questions and Answers

Enthalpy is a thermodynamic property that represents the total heat content of a system.

• Enthalpy is denoted by the symbol H.

• It is defined as the sum of the internal energy of a system and the product of its pressure and volume.

• The formula for enthalpy is H = U + PV, where U is the internal energy, P is the pressure, and V is the volume.

• Enthalpy is often used in chemical reactions to measure the heat exchanged with the surroundings.

• It can be used to calculate the heat absorbed...read more

Slider crank mechanism is a simple mechanism used to convert rotary motion into reciprocating motion.

• Consists of a slider, crank, connecting rod and a shaft

• Used in engines, pumps, compressors, etc.

• The slider moves back and forth in a straight line

• The crank rotates in a circular motion

• The connecting rod connects the slider and the crank

• The shaft provides the rotary motion

• The mechanism is used to convert the reciprocating motion of the piston in an engine into rotary motion of ...read more

Laws governing energy and its transformations in physical systems.

• First law: Energy cannot be created or destroyed, only transferred or converted.

• Second law: Entropy of an isolated system always increases over time.

• Third law: Absolute zero cannot be reached by any finite number of processes.

• Applications in engineering, physics, chemistry, and biology.

• Examples include heat engines, refrigeration, and combustion processes.

Entropy is a measure of disorder or randomness in a system.

• Entropy is denoted by the symbol S.

• The formula for entropy is S = k ln W, where k is the Boltzmann constant and W is the number of possible microstates.

• Entropy increases with an increase in the number of microstates.

• Entropy is a state function and is independent of the path taken to reach a particular state.

• Entropy has units of J/K (joules per kelvin).

Bernoulli's theorem states that as the speed of a fluid increases, its pressure decreases.

• The theorem is based on the conservation of energy in a fluid system.

• It is commonly used in fluid dynamics to calculate the pressure and velocity of fluids in motion.

• The theorem is applicable to both incompressible and compressible fluids.

• An example of Bernoulli's theorem in action is the lift generated by an airplane wing.

• The theorem is named after Swiss mathematician Daniel Bernoulli w...read more