Mechanical Engineering BDL MT Mock Test - 4 Free Online Test 2026

If a liquid (pure substance) is heated at constant pressure, the temperature at which it boils is called saturation temperature. This temperature will remain constant during heating until all the liquid boils off. At this temperature, the liquid and the associated vapour at the same temperature are in equilibrium and are called saturated liquid and vapour, respectively. The saturation temperature of a pure substance is a function of pressure only. At atmospheric pressure, the saturation temperature is called the normal boiling point. Similarly, if the vapour of a pure substance is cooled at constant pressure, the temperature at which the condensation starts is called dew point temperature.

Similarly, when a solid is heated at constant pressure, it melts at a definite temperature called the melting point.

An Isobaric process is a thermodynamic process in which the pressure stays constant: ΔP = 0. The heat transferred to the system does work but also changes the internal energy of the system. This article uses the physics sign convention for work, where positive work is work done by the system.

The solar energy received by the earth is approximately 1.4 kW/m². It is known as solar constant or Solar Irradiance.

A gas-turbine power plant operates on the simple Brayton cycle between the pressure limits of 100 and 1600 KPa. The working fluid is a mixture of air with 20% of carbon monoxide (CO). The mixture enters the compressor at 40^oC at a rate of 850 m3/min and leaves the turbine at 650^oC.

In uniform gravity, it is the same as the centre of mass. For regular-shaped bodies, it lies at the centre of that particular body. Hence for a cylinder centre of gravity lies at the midpoint of the axis of the cylinder.

Mandrel is used to hold a hollow bar or a bar with a bore wen turning between live centre and dead cente of a lathe. A moving mandrel is also used for tube drawing

From the lead screw, the motion is transmitted to the carriage by engaging the half nut with the lead screw.

The cutting tool moves with the lathe carriage by the engagement of a half nut with the lead screw.

Acme threads are used in lathe lead screws. This form of thread enables the easy engagement of the half nut.

Example of firing tube boilers:

• Cornish boiler

• Cochran boiler

• Locomotive boiler

• Lancashire boiler

• Scotch marine boiler

Water Tube Boiler: In this boiler, water is present inside the tubes, and the hot flue gases surround them. They are high-pressure boilers, and the operating pressure is about 250 bar.

• Stirling boiler

• Babcock and Wilcox boiler

• Yarrow boiler

• Lamont boiler

• Loeffler boiler

Everything has mass, and thus, everything that moves must have momentum because its mass in motion! Now, if momentum is "mass in motion,” then what's inertia?

Inertia is the RESISTANCE an object has a quality of an object to keep that object at rest if it is at rest and to keep it moving in uniform motion if it is moving in uniform motion.

He observed that the volume of a given mass of a gas is inversely proportional to its pressure at a constant temperature. Boyle's law, published in 1662, states that, at a constant temperature, the product of the pressure and volume of a given mass of an ideal gas in a closed system is always constant.

F_AB = W cosec θ

F_BC = F_AB cos θ = W cosec θ × cos θ

F_BC = = W cot θ

The efficiency of a centrifugal pump will be maximum when the blades are bent backward.

The no. of triangles = 5

Hence, 5 is the correct answer.

P is from Syndicate Bank.

8 × 7 × 8 = 448

Similarly,

6 × 3 × 8 = 144

Therefore 144 is the correct answer.

4 × 5 = 20

5 × 6 = 30

6 × 7 = 42

7 × 8 = 56

8 × 9 = 72

9 × 10 = 90

Hence, 90 is the correct answer.

The person from the Bank of Maharashtra is an immediate neighbor of A.

⇒ 70/100 x (a - b) = 40/100 x (a + b)

⇒ 7a - 7b = 4a + 4b

⇒ 7a - 4a = 4b + 7b

⇒ 3a = 11b

⇒ a/b = 11/3

⇒ a:b = 11:3

Let fraction be x/y by given condition

∴ (x + y + z)² = 9² = 81

∴ x² + y² + z² + 2 × 26 = 81

∴ x² + y² + z² = 81 - 52 = 29

Now, x³ + y³ + z³ - 3xyz

= (x + y + z) [(x² + y² + z²)] - (xy + yz + xz)]

= 9 × (29 - 26) = 27

If the work is to be finished in 5 days, number of women required = 15

If the work is to be finished in 6 days, number of women required =[15×5]/6 = 25/2

So that 10 men = 25/2 women

or 5 women = 4 men

8 men + 5 women = 8 men + 4 men = 12 men

Now 10 men can finish the work in = 6 days

∴ 12 men can finish the work in [6×10]/12=5 days

Option 1 is eliminated as 'listening' must be followed with the preposition 'to' which is not present here. Option 3 is incorrect as 'famous' cannot fit in the second blank. The word here has to be a verb. Option 4 does not convey a logical meaning. Option 2 conveys a proper meaning. The man listened to folk tales of places and used them for composing his songs.

The second option is the answer. Debacle is a sudden fail or collapse. Ricochet is bouncing back, projection is displaying and instantaneous means something that has happened suddenly.
Thus, debacle is the right word.

The sentence is present in passive voice. Here, the subject and object are 'The king' and the 'enemy', who would exchange places with each other. Since both the past participle and past tense form of the verb 'to overpower' is 'overpowered', it will be used in place of 'was+past participle of the verb'.

Therefore, the correct answer is option 3.

The subject is written before the object in active voice.

subject +verb +object

The correctly structured sentence is option 3 as 'did not make' is correct here.Option 3 is thus the correct answer

In indirect speech the words of the speaker are not written in quotes. Usually the word 'that' is used to convey the words of the speaker. The correct tense should be simple past as the tense in direct speech is simple present. Option 3 is the correct answer.