Home
Current Affairs January 2024

What is the correct answer?

4

Workdone during adiabatic expansion is given by (where p1 v1, T1 = Pressure, volume and temperature for the initial condition of gas, p2, v2, T2 = Corresponding values for the final condition of gas, R = Gas constant, and γ = Ratio of specific heats)

A. (p1 v1 - p2 v2)/(γ - 1)

B. [m R (T1 - T2)] /(γ - 1)

C. [m R T1/(γ - 1)][1 - (p2 v2 /p1 v1)]

D. All of these

Correct Answer :

D. All of these


Related Questions

What is the correct answer?

4

The absolute zero temperature is taken as

A. 237°C

B. -273°C

C. -237°C

D. 273°C

What is the correct answer?

4

The following cycle is used for air craft refrigeration

A. Brayton cycle

B. Joule cycle

C. Carnot cycle

D. Reversed Brayton cycle

What is the correct answer?

4

The section modulus of a circular section about an axis through its C.G., is

A. πd²/4

B. πd²/16

C. πd3/16

D. πd3/32

What is the correct answer?

4

A shaft revolving at ω rad/s transmits torque (T) in Nm. The power developed is

A. T.ω watts

B. 2π. T.ω watts

C. 2π. T.ω/75 watts

D. 2π. T.ω/4500 watts

What is the correct answer?

4

Impact strength of a material is an index of its

A. Toughness

B. Tensile strength

C. Capability of being cold worked

D. Hardness

What is the correct answer?

4

When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the minimum normal stress is

A. x/2) + (1/2) × √(σx² + 4 τ²xy)

B. x/2) - (1/2) × √(σx² + 4 τ²xy)

C. x/2) + (1/2) × √(σx² - 4 τ²xy)

D. (1/2) × √(σx² + 4 τ²xy)

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 minimum 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

Mond gas is obtained by

A. Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast

B. Carbonisation of bituminous coal

C. Passing steam over incandescent coke

D. Passing air and a large amount of steam over waste coal at about 650°C

What is the correct answer?

4

When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.

A. Atomisation

B. Carbonisation

C. Combustion

D. None of these

What is the correct answer?

4

A series of operations, which takes place in a certain order and restore the initial conditions at the end, is known as

A. Reversible cycle

B. Irreversible cycle

C. Thermodynamic cycle

D. None of these

What is the correct answer?

4

The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is

A. Same

B. Twice

C. Four times

D. Eight times

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 efficiency of Carnot cycle is maximum for

A. Gas engine

B. Petrol engine

C. Steam engine

D. Reversible engine

What is the correct answer?

4

The efficiency of Diesel cycle with decrease in cut-off

A. Increases

B. Decreases

C. First increases and then decreases

D. First decreases and then increases

What is the correct answer?

4

The natural solid fuel is

A. Wood

B. Coke

C. Anthracite coal

D. Pulverised coal

What is the correct answer?

4

In closed cycle gas turbine, the air is compressed

A. Isothermally

B. Isentropically

C. Polytropically

D. None of these

What is the correct answer?

4

The bending moment at a point on a beam is the algebraic ________ of all the moments on either side of the point.

A. Sum

B. Difference

C. Multiplication

D. None of the above

What is the correct answer?

4

According to Kelvin-Planck's statement of second law of thermodynamics,

A. It is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work

B. It is possible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work

C. It is impossible to construct a device which operates in a cyclic process and produces no effect other than the transfer of heat from a cold body to a hot body

D. None of the above

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

The most probable velocity of the gas molecules is given by

A. √(KT/m)

B. √(2KT/m)

C. √(3KT/m)

D. √(5KT/m)

What is the correct answer?

4

The efficiency of Joule cycle is

A. Greater than Carnot cycle

B. Less than Carnot cycle

C. Equal to Carnot cycle

D. None of these

What is the correct answer?

4

An open system is one in which

A. Heat and work crosses the boundary of the system, but the mass of the working substance does not crosses the boundary of the system

B. Mass of the working substance crosses the boundary of the system but the heat and work does not crosses the boundary of the system

C. Both the heat and work as well as mass of the working substance crosses the boundary of the system

D. Neither the heat and work nor the mass of the working substance crosses the boundary of the system

What is the correct answer?

4

Coke is produced

A. When coal is first dried and then crushed to a fine powder by pulverising machine

B. From the finely ground coal by moulding under pressure with or without a binding material

C. When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel

D. By heating wood with a limited supply of air to a temperature not less than 280°C

What is the correct answer?

4

The specific heat at constant volume is

A. The amount of heat required to raise the temperature of unit mass of gas through one degree, at constant pressure

B. The amount of heat required to raise the temperature of unit mass of gas through one degree, at constant volume

C. The amount of heat required to raise the temperature of 1 kg of water through one degree

D. Any one of the above

What is the correct answer?

4

Kerosene is distilled at

A. 65° to 220°C

B. 220° to 345°C

C. 345° to 470°C

D. 470° to 550°C

What is the correct answer?

4

The stress induced in a body due to suddenly applied load compared to when it is applied gradually is

A. Same

B. Half

C. Two times

D. Four times

What is the correct answer?

4

The variables which control the physical properties of a perfect gas are

A. Pressure exerted by the gas

B. Volume occupied by the gas

C. Temperature of the gas

D. All of these

What is the correct answer?

4

A beam is loaded as cantilever. If the load at the end is increased, the failure will occur

A. In the middle

B. At the tip below the load

C. At the support

D. Anywhere

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

The energy absorbed in a body, when it is strained within the elastic limits, is known as

A. Strain energy

B. Resilience

C. Proof resilience

D. Modulus of resilience