Home
Current Affairs January 2024

What is the correct answer?

4

The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as

A. Enthalpy

B. Internal energy

C. Entropy

D. External energy

Correct Answer :

C. Entropy


Related Questions

What is the correct answer?

4

Which of the following materials is most elastic?

A. Rubber

B. Plastic

C. Brass

D. Steel

What is the correct answer?

4

The torsional rigidity of a shaft is expressed by the

A. Maximum torque it can transmit

B. Number of cycles it undergoes before failure

C. Elastic limit up to which it resists torsion, shear and bending stresses

D. Torque required to produce a twist of one radian per unit length of shaft

What is the correct answer?

4

During which of the following process does heat rejection takes place in Carnot cycle?

A. Isothermal expansion

B. Isentropic expansion

C. Isothermal compression

D. Isentropic compression

What is the correct answer?

4

Which is the incorrect statement about Carnot cycle?

A. It is used as the alternate standard of comparison of all heat engines.

B. All the heat engines are based on Carnot cycle.

C. It provides concept of maximising work output between the two temperature limits.

D. All of the above

What is the correct answer?

4

When a body is subjected to biaxial stress i.e. direct stresses (σx) and (σy) in two mutually perpendicular planes accompanied by a simple shear stress (τxy), then maximum normal stress is

A. x + σy)/2 + (1/2) × √[(σx - σy)² + 4 τ²xy]

B. x + σy)/2 - (1/2) × √[(σx - σy)² + 4 τ²xy]

C. x - σy)/2 + (1/2) × √[(σx + σy)² + 4 τ²xy]

D. x - σy)/2 - (1/2) × √[(σx + σy)² + 4 τ²xy]

What is the correct answer?

4

The absolute zero pressure can be attained at a temperature of

A. 0°C

B. 273°C

C. 273 K

D. None of these

What is the correct answer?

4

One molecule of oxygen consists of __________ atoms of oxygen.

A. 2

B. 4

C. 8

D. 16

What is the correct answer?

4

The efficiency of Diesel cycle approaches to Otto cycle efficiency when

A. Cut-off is increased

B. Cut-off is decreased

C. Cut-off is zero

D. Cut-off is constant

What is the correct answer?

4

The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is

A. Equal to one

B. Less than one

C. Greater than one

D. None of these

What is the correct answer?

4

One kg of carbon produces __________ kg of carbon dioxide.

A. 3/7

B. 7/3

C. 11/3

D. 3/11

What is the correct answer?

4

According to Kelvin-Planck's statement, a perpetual motion of the __________ is impossible.

A. First kind

B. Second kind

C. Third kind

D. None of these

What is the correct answer?

4

Principal planes are planes having

A. Maximum shear stress

B. No shear stress

C. Minimum shear stress

D. None of the above

What is the correct answer?

4

The general law of expansion or compression is pvn = C, The process is said to be hyperbolic, if n is equal to

A. 0

B. 1

C. γ

D.

What is the correct answer?

4

The compression ratio for petrol engines is

A. 3 to 6

B. 5 to 8

C. 10 to 20

D. 15 to 30

What is the correct answer?

4

Which of the following statement is correct according to Clausis statement of second law of thermodynamics?

A. It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature.

B. It is impossible to transfer heat from a body at a lower temperature to a body at a higher temperature, without the aid of an external source.

C. It is possible to transfer heat from a body at a lower temperature to a body at a higher temperature by using refrigeration cycle.

D. None of the above

What is the correct answer?

4

The weakest section of a diamond riveting is the section which passes through

A. The first row

B. The second row

C. The central row

D. One rivet hole of the end row

What is the correct answer?

4

The volumetric or molar specific heat at constant pressure is the product of

A. Molecular mass of the gas and the specific heat at constant volume

B. Atomic mass of the gas and the gas constant

C. Molecular mass of the gas and the gas constant

D. None of the above

What is the correct answer?

4

One reversible heat engine operates between 1600 K and T2 K and another reversible heat engine operates between T2 K and 400 K. If both the engines have the same heat input and output, then temperature T2 is equal to

A. 800 K

B. 1000 K

C. 1200 K

D. 1400 K

What is the correct answer?

4

The gas in cooling chamber of a closed cycle gas turbine is cooled at

A. Constant volume

B. Constant temperature

C. Constant pressure

D. None of these

What is the correct answer?

4

The stress induced in a body, when suddenly loaded, is ________ the stress induced when the same load is applied gradually.

A. Equal to

B. One-half

C. Twice

D. Four times

What is the correct answer?

4

When it is indicated that a member is elastic, it means that when force is applied, it will

A. Not deform

B. Be safest

C. Stretch

D. Not stretch

What is the correct answer?

4

Hooke's law holds good up to

A. Yield point

B. Limit of proportionality

C. Breaking point

D. Elastic limit

What is the correct answer?

4

An isothermal process is governed by

A. Boyle's law

B. Charles' law

C. Gay-Lussac law

D. Avogadro's law

What is the correct answer?

4

According to kinetic theory of gases, the velocity of molecules __________ with the increase in temperature.

A. Remains constant

B. Increases

C. Decreases

D. None of these

What is the correct answer?

4

Kelvin-Planck's law deals with

A. Conservation of work

B. Conservation of heat

C. Conversion of heat into work

D. Conversion of work into heat

What is the correct answer?

4

The neutral axis of the cross-section a beam is that axis at which the bending stress is

A. Zero

B. Minimum

C. Maximum

D. Infinity

What is the correct answer?

4

The natural petroleum may be separated into

A. Petrol

B. Kerosene

C. Fuel oil

D. Lubricating oil

What is the correct answer?

4

When a body is subjected to three mutually perpendicular stresses, of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known as

A. Young's modulus

B. Modulus of rigidity

C. Bulk modulus

D. Poisson's ratio

What is the correct answer?

4

The cycle in which heat is supplied at constant volume and rejected at constant pressure is known as

A. Dual combustion cycle

B. Diesel cycle

C. Atkinson cycle

D. Rankine cycle

What is the correct answer?

4

One molecule of oxygen is __________ times heavier than the hydrogen atom.

A. 12

B. 14

C. 16

D. 32