HPCL Mechanical Engineer Mock Test - 9 Free Online Test 2026

• The area of a rhombus is calculated using the two diagonals.
• Dividing the rhombus along its diagonals creates four right triangles.
• Thus, the formula becomes 1/2 multiplied by the product of d1 and d2.
• Answer d, which represents 1/2 (d1 x d2), is correct.

First, find the normal rate of Pipe A:

• Pipe A fills 1000 liters in 150 minutes.
• Hence, its normal rate = 1000 / 150 = 6.6667 liters per minute.

Next, if it works at only 5% efficiency, its rate becomes:

• 5% of 6.6667 = 0.05 × 6.6667 = 0.3333 liters per minute (approximately).

Finally, to fill 60 liters at this reduced rate:

• Time required = 60 / 0.3333 ≈ 180 minutes.

Answer: 180 minutes (Option c).

Hence, Option C is correct.

Option D is correct.

Assumption: the endpoints are excluded so the smallest even number is 2 and the largest even number is 48.

Number of terms (n) = (last - first)/difference + 1 = (48 - 2)/2 + 1 = 24.

Average = (first + last)/2 = (2 + 48)/2 = 25.

Therefore the average is 25, so the correct option is D.

Sum of 100 numbers =100×210=21000
Sum of 120 numbers =120×200=24000
Sum of 20 numbers =24000−21000=3000
∴ Average of 20 new numbers =3000/20=150

Hence, Option D is correct.

Let AB be the post and AC be its shadow.
Let AB = X m. Then, AC = √3Xm.Let∠ACB = θ.
AB/AC = tanθ => tanθ = X/√3X = 1/√3 = tan30°.
∴ θ = 30°.
Hence, the point of rise is 30°.

∠DAC = ∠B + ∠C
(Exterior angle prop. of a Δ ABC)
According to question,
130° = 2A + 3A
5A = 130°
A = 26°
∴ ∠B = 52°; ∠C = 78°

Hence, Option A is correct.

Perimeter of the wheel

Hence, Option B is correct.

Hence, Option B is correct.

Let the required number be x.
As given,

2ⁿ(2⁴-2) + 2^-3
2ⁿx2x2³
14 + 2^-3
2⁴
7/8+1/8
1

When the denominator of an expression contains a term with a square root, the process of converting it to an equivalent expression whose denominator is a rational number is called rationalising the denominator.
By multiplying we will get same expression since 
Therefore, 

1) 8, 4, 3, 7, 1, 5, 2, 6

2) 5, 2, 7, 3, 4, 1, 8, 6

3) 3, 1, 6, 8, 4, 5, 2, 7

4) 1, 4, 8, 3, 2, 5, 7, 6

'POLITICS' is a meaningful English word.

Hence, '1, 4, 8, 3, 2, 5, 7, 6' is the correct answer.

From Statement I: From this statement, we get the following diagram

Clearly, Statement I alone is not sufficient to answer the question.

From Statement II: From this statement, we get following diagram

Clearly, Statement II alone is not sufficient to answer the question.

Checking both Statement, I and II together:

Here, on merging both the statements we get the following diagram,

So, by combining both the statements, we can say J sits 3rd to the left of N, who visited W..

Clearly, Statement I and Statement II together are necessary to answer the question.

Hence, option E is the correct answer.
 

First and fouth letters are interchanged while second and third letters are interchanged.

As Water of a River flows similarly water of Pool is Stagnant.

The logic follows here is:

In fig 1:

12 = 6 ÷ 2 × 4

12 = 3 × 4 

12 = 12

In fig 2:

80 = 20 ÷ 2 × 8

80 = 10 × 8

80 = 80

Similarly,

63 = ? ÷ 2 × 21

63 / 21 = ? ÷ 2

3 = ? ÷ 2

? = 3 × 2

? = 6

Hence, the correct answer is "6".

From the common explanation, we get T sits immediate right of Q.
Hence, Option B is correct.
Final Arrangement:

Common Explanation:
References:
Exactly two persons are sitting between P and Q.
Only one person is sitting between P and U.
Inferences:
From the above references, we get two different cases:

References:
S is sitting second to the right of R.
Inferences:
From the above reference, we get the following arrangements:

References:
T is not sitting beside S.
Inferences:
So, from this case 2 will be eliminated as T is not sitting beside S.
Hence, we get our final arrangement:

A Priest wears cassock (a full-length garment worn by certain Christian clergy, members of church choirs, and others having an office or role in a church.) while Graduate wears gown.

Given:

x + 1/x = 25

Concept Used:

If x + 1/x = p then, x – 1/x = √(p² – 4)

Calculation:

It is given that x + 1/x = 25

 We know that if x + 1/x = p then, x – 1/x = √(p² – 4)

⇒ x – 1/x = √(25² – 4)

⇒ x – 1/x = √(625 – 4)

⇒ x – 1/x = √621

According to the given information:

So, the cube of the number 2 is 8.

But in the statement, 'eight' is called 'nine'.

Hence, the correct answer is "Nine".

P sits to the immediate left of S.

Hence, option A is correct.

Hence, option A is correct.

Among the given options:

• Mathura, Allahabad, and Varanasi are all known as important religious cities in India, especially for Hindus.
• Kanpur is mainly recognised as an industrial city and is not famous for religious significance like the others.

So, Kanpur is the word that is different from the rest.

Quality-Based Governing: In this type of engines, we can control the air-fuel ratio or quality of the air-fuel mixture. This is done in the case of diesel engines, where the fuel is introduced inside the cylinder by fuel injection.

Quantity Based Governing: In this type of engine, we can not control the air-fuel ratio by any means. We can control the volume of the mixture supplied to the engine. This is employed in SI engines.

A poppet valve (also called a mushroom valve) is a valve typically used to control the timing and quantity of gas or vapor flow into an engine. It consists of a hole, usually round or oval, and a tapered plug, usually a disk shape on the end of a shaft also called a valve stem.

For a thin spherical pressure vessel, both longitudinal and hoop stress is the same and given as

Compressor: The compressor is located at the back of the refrigerator and in the bottom area. The compressor sucks the refrigerant from the evaporator and discharges it at high pressure and temperature. The compressor is driven by the electric motor, and it is the major power-consuming device of the refrigerator.

Condenser: The condenser is the thin coil of copper tubing located at the back of the refrigerator. The refrigerant from the compressor enters the condenser,stress-strain where it is cooled by the atmospheric air, thus losing heat absorbed by it in the evaporator and the compressor.

Expansive valve or the capillary: The refrigerant leaving the condenser enters the expansion device, which is the capillary tube in domestic refrigerators. The capillary is the thin copper tubing made up of a number of turns of the copper coil. When the refrigerant is passed through the capillary, its pressure and temperature drop down suddenly.

Evaporator or chiller or freezer: The refrigerant at very low pressure and temperature enters the evaporator or the freezer. It is the coldest part of the refrigerator. The refrigerant absorbs the heat from the substance to be cooled in the evaporator, gets evaporated, and is then sucked by the compressor. This cycle keeps on repeating.

Receiver: The primary function of the receiver is to catch and hold any liquid refrigerant that didn’t boil off in the evaporator. Liquid refrigerant getting to the compressor can damage the pistons.

In the Power screw, the torque Mt required to lower the load is given by

M_t = Wd_m/2 tan (ϕ−α) where, W = load on the screw in N, d_m = the mean diameter of the screw-in m,

ϕ = friction angle and α = helix angle

Case 1. when ϕ ≥ α

tan (ϕ - α ) ≥ 0, thus M_t ≥ 0.

i.e., positive torque is required to lower the load. Thus the load will not turn the screw and will not descend on its own unless an effort is applied.

Such cases of screws are known as 'Self-locking screws.’ And the screw will hold the hold without any application of the brake.

Also, as ϕ ≥ α

tan ϕ ≥ tan α

Case 2. when ϕ <>

tan (ϕ - α ) < 0,="" thus="">_t <>

i.e., negative torque is required to lower the load. The load will turn down the screw and will descend on its own unless a restoring torque is required to hold the load.

Such cases of screws are known as 'overhauling of the screw' or back drawing of the screw.