BPSC AE 2025: Assistant Engineer (Civil/Mechanical/Electrical) (Advt. 30/2025), Paper V Mechanical Engineering

Bihar Public Service Commission
    Advt. No. 30/2025, Mechanical Engineering Paper-V
             Exam Date: 19-07-2025, 1st Shift
                  Final Answer key (Set-I)
Question No.       Ans. Key       Question No.    Ans. Key
     1                C                26               D
     2                D                27               B
     3                C                28               C
     4                B                29         Deleted
     5                B                30               A
     6                D                31               A
     7                C                32               D
     8                A                33               B
     9                A                34         Deleted
    10                C                35               D
    11                B                36               C
    12                D                37               D
    13                B                38               D
    14                D                39               C
    15                A                40               A
    16                C                41               B
    17                A                42               B
    18                B                43               D
    19                B                44         Deleted

Question No.   Ans. Key       Question No.   Ans. Key

    20            D               45            C
    21            B               46            A
    22            D               47            A
    23            D               48            D
    24            A               49            C
    25            B               50            A


                      (Set – J)
Question No.   Ans. Key       Question No.   Ans. Key
     1            A               26            B
     2            D               27            B
     3            C               28            A
     4            D               29            D
     5            A               30            B
     6            A               31            D
     7            A               32            B
     8            C               33            B
     9            A               34         Deleted
    10            D               35            C
    11            C               36            D
    12            B               37            A
    13            C               38            C
    14            A               39            B
    15            D               40            C

Question No.   Ans. Key       Question No.   Ans. Key

    16            B               41         Deleted
    17            C               42            D
    18            C               43            A
    19            D               44            C
    20            C               45            B
    21            A               46            B
    22            C               47         Deleted
    23            D               48            A
    24            B               49            D
    25            A               50            D


                      (Set – K)
Question No.   Ans. Key      Question No.    Ans. Key
     1            C               26            A
     2            D               27            A
     3            D               28            D
     4            C               29         Deleted
     5            D               30            C
     6            A               31            C
     7            C               32            C
     8            D               33            D
     9            D               34            C
    10            B               35            B
    11            B               36            D

Question No.   Ans. Key       Question No.   Ans. Key

    12            D               37            A
    13            A               38            B
    14            A               39            B
    15            A               40         Deleted'
    16         Deleted            41            B
    17            B               42            C
    18            A               43            D
    19            D               44            B
    20            A               45            B
    21            B               46            C
    22            D               47            C
    23            C               48            A
    24            C               49            B
    25            C               50            D


                      (Set – L)
Question No.   Ans. Key      Question No.    Ans. Key
     1            C               26            B
     2            A               27            D
     3            A               28            C
     4            B               29            C
     5            C               30            A
     6            C               31            D
     7            A               32            A

Question No.              Ans. Key              Question No.             Ans. Key
            8                     C                       33                     C
            9                     A                       34                     B
           10                     D                       35                     A
           11                     B                       36                     D
           12                     C                       37                     C
           13                     D                       38                     D
           14                     D                       39                     D
           15                     B                       40                     B
           16                     A                       41                     D
           17                     B                       42                     A
           18                     B                       43                     B
           19                     D                       44                     D
           20                     C                       45                     A
           21                 Deleted                     46                 Deleted
           22                     D                       47                     D
           23                 Deleted                     48                     A
           24                     A                       49                     B
           25                     C                       50                     A


                               Reason as per Set- I

Q.No.- 07- The Provisional answer is option 'B' but the correct answer is option 'C'.
Reason :- The Value of k is higher in U-bend than 90o - bend so maximum head
           loss will occur on U-bend.
           Ref. fluid power with application, 7th edition ISBN. 9780135136904 by
           Anthony Esposito, Pearson Pub.

Q.No.- 17 - No Change.
Reason :- Ref.1- Thermal Engg. by Mahesh M Rathore. Page-692 McGraw Hill
            education pvt.ltd. 2018.
            Ref.2- Power plant engg. by P.K.Nag.
Q.No.- 19 - No Change.
Reason :- 'May be' In question no. 19 sensed as regenerating arrangement in
            stirling cycle that allows its efficiency to be same as that of carnot cycle
            running between same temp. limits.
            Ref.- Basic and applied thermodynamics by P.K.Nag
Q.No.- 29- Deleted.
Reason :- There is typo error in the question where pressure ratio term is missing,
            also there are typo errors in the option of the solution where (γ-1) term is
            missing. Hence, the question is deleted.
Q.No.- 34- Deleted.
Reason :- Both option B & D are correct. So the question is deleted.
Q.No.- 39- The Provisional answer is option 'B' but the correct answer is option 'C'.
Reason :- Ref.- I.C Engine ,V.Ganeshan,
Q.No.- 44- Deleted.
Reason :- Multiple options are correct. Hence, the question is deleted.
Q.No.- 46- No Change.
Reason :- Ref. Internal Combustion Engine by V.M and A.V Domkundwar
            Dhanpat Rai & co publication.
Q.No.- 48- The Provisional answer is option 'B' but the correct answer is option 'D'.
Reason :- Ref. Heat Engineering by V.P. Vasandani, Metropolitan Pub.