Explore topic-wise MCQs in Coal India.

This section includes 49 Mcqs, each offering curated multiple-choice questions to sharpen your Coal India knowledge and support exam preparation. Choose a topic below to get started.

1.

The correct way to round off a floating number x to an integer value is

A. y = int (x + 0.5)
B. y = (int) (x + 0.5)
C. y = (int) x + 0.5
D. y = (int) ((int)x + 0.5)
Answer» C. y = (int) x + 0.5
2.

What does the following declaration mean? int (*ptr) [10];

A. ptr is an array of pointers of 10 integers.
B. ptr is a pointer to an array of 10 integers.
C. ptr is an array of 10 integers.
D. None of the above
Answer» C. ptr is an array of 10 integers.
3.

How to make an infinity loop in C?

A. loop: ..... goto loop;
B. for(;;) { }
C. while(1) { }
D. All of the above
Answer» E.
4.

Type of data and its value is described dy

A. Constants
B. Variables
C. Data Type
D. None of the above
Answer» C. Data Type
5.

The Case keyword is followed by?

A. Float values
B. Character values
C. Integer values
D. Both b&c
Answer» E.
6.

  A full binary tree with n leaves contains

A. n nodes
B. 2n - 1 nodes
C. log2 n nodes
D. 2n nodes
Answer» C. log2 n nodes
7.

Which of the following storage classes have global visibility in C?

A. Auto
B. Static
C. Extern
D. Register
Answer» D. Register
8.

How many times is a do while loop guaranteed to loop?

A. 0
B. Variable
C. 1
D. Infinitely
Answer» D. Infinitely
9.

  Which of the following sorting algorithms does NOT have a worst-case running time of O(n2)?

A. Insertion sort
B. Merge sort
C. Quicksort
D. Bubble sort
Answer» C. Quicksort
10.

  Which data structure type is NOT linear from the following?

A. Doubly Link List
B. 2D Array
C. Binary Search Tree
D. Queue
Answer» D. Queue
11.

What is the purpose of getc()  

A. read a character from STDIN
B. read a character from a file
C. read all file
D. read file randomly
Answer» C. read all file
12.

  Which of the following is not an iterative statement

A. while
B. do while
C. switch
D. for
Answer» D. for
13.

  Which is an invalid name of identifier?

A. world
B. addition23
C. test-name
D. factorial
Answer» D. factorial
14.

  Which of these assignments is invalid?

A. short s = 48;
B. float f = 4.3;
C. double d = 4.3;
D. int I = `1`;
Answer» E.
15.

Which logic gate has output high if and only if all inputs are low ———?

A. NOR
B. NAND
C. X-NOR
D. AND
Answer» C. X-NOR
16.

How many NAND gates are needed to realize OR gate ————–  

A. 1
B. 2
C. 3
D. 4
Answer» D. 4
17.

By adding inverters to the inputs and output of a AND gate we can obtain ……………  

A. OR
B. AND
C. NOT
D. X-OR
Answer» E.
18.

which logic gate has the output is compliment of its input ———-

A. OR
B. AND
C. NOT
D. X-OR
Answer» D. X-OR
19.

how many flip-flops are required to construct Mod -12 counter

A. 5
B. 4
C. 12
D. none
Answer» C. 12
20.

the radix or base of hexadecimal number system is ———–

A. 8
B. 16
C. 5
D. none of these
Answer» C. 5
21.

Convert the 101101 Binary number into octal no

A. 65
B. 55
C. 51
D. 45
Answer» C. 51
22.

Which one of the following is not a semiconductor?

A. Diamond
B. Galtium‐Arsenide
C. Silicon
D. Germanium
Answer» B. Galtium‐Arsenide
23.

A Zenor Diode is invariably used with

A. Forward bias
B. Reverse bias
C. Zero bias
D. Either of A or C
Answer» C. Zero bias
24.

The relation between the number of pairs (p) forming a kinematic chain and the number of links (k) is given by

A. K = p = 1
B. K= 2p – 2
C. K = 2p – 3
D. K = 2p ‐4
Answer» B. K= 2p – 2
25.

The Factories employing more than 1000 workers are required to submit their plan for approval to

A. Deputy Chief Inspector of Factories
B. Joint Chief Inspector of Factories
C. Chief Inspector of Factories
D. Additional Chief Inspector of Factories
Answer» D. Additional Chief Inspector of Factories
26.

A general manager of a company can be appointed as a occupier of a company.

A. True
B. False
Answer» C.
27.

Where ————or more workers are employed in a factory, then there shall be a Safety Committee in the factory.

A. 100 or more workers
B. 150 or more workers
C. 200 or more workers
D. 250 or more workers
Answer» E.
28.

Which one of the following would qualify to be a strategic HRM activity?

A. Administer Wage & Salary Programmes
B. Prepare Staffing Plans
C. Determine the level & type of Performance that is crucial for firm’s growth
D. Use specific job skill training
Answer» D. Use specific job skill training
29.

Which one of the following is not a valid Wage Theory?

A. The Just Wage Theory
B. Subsistence Theory
C. Standard of Living Theory
D. Best Wage Theory
Answer» E.
30.

The phase lead compensation is used t

A. Increase rise time and decrease overshoot
B. Decrease both rise time and overshoot
C. Increase both rise time and overshoot
D. Decrease rise time and increase overshoot
Answer» E.
31.

i. (X’+Y’) A. Low-pass filter function ii. (X’Y’) B. Sum iii. (XY) C. NAND D. Carry E.NOR

A. i-C, ii-E, iii-D
B. i-C, ii-E, iii-B
C. i-C, ii-B, iii-D
D. i-C, ii-E, iii-A
Answer» B. i-C, ii-E, iii-B
32.

In Gauss Seidel method the following factors are influenced for operation

A. Acceleration factor
B. Selection of slack buss
C. Both
D. None
Answer» C. Both
33.

When sine wave is given as input to Schmitt trigger then its generates

A. Sine wave
B. Saw tooth wave
C. Triangle wave
D. Square wave
Answer» E.
34.

Hays bridge is used to measure___________ and Schering bridge is used to measure____________

A. Inductance, Inductance
B. Inductance, Capacitance
C. Capacitance, Inductance
D. Resistance, Capacitance
Answer» C. Capacitance, Inductance
35.

The two watt meters measurement the ratio of two meter readings is –(1-sqrt3):( 1+sqrt3) then the power factor is

A. 1
B. 0.866
C. 0.707
D. 0
Answer» D. 0
36.

Thermocouple is used to measure

A. AC
B. DC
C. Both
D. None
Answer» D. None
37.

A 3-phase 50HZ SCIM takes a power input of 30 KW at its full load speed of 1440 rpm. Total stator losses are 1 KW. The slip and rotor ohmic losses at full load are

A. 0.02, 600 W
B. 0.04, 580 W
C. 0.04, 1160 W
D. 0.04, 1200 W
Answer» D. 0.04, 1200 W
38.

A CRO screen has ten divisions on the horizontal scale. If a voltage signal 5 sin 314t+45 deg)is examined with a line base settings of 5 msec/div, the number of cycles of signal displayed on the screen will be

A. 0.5 cycles
B. 2.5 cycles
C. 5 cycles
D. 10 cycles
Answer» C. 5 cycles
39.

In an induction machine, if the air gap increased

A. Speed will be reduced
B. Efficiency will be improved
C. Power factor will be lowered
D. Breakdown torque will be reduced
Answer» D. Breakdown torque will be reduced
40.

Moving coil in dynamometer wattmeter connected

A. In series with fixed coil
B. Across supply
C. In series with load
D. Across load
Answer» C. In series with load
41.

A dc cumulatively compounded motor delivers rated load torque at rated speed. If series field is short circuited, then the armature current and speed will

A. Both increases
B. Both decreases
C. Increases and decreases
D. Decreases and increases
Answer» B. Both decreases
42.

A 0-10 mA PMMC ammeter reads 5mA in a circuit; its bottom control spring snaps out suddenly the meter will now read.

A. 5mA
B. 10mA
C. 2.5mA
D. 0
Answer» E.
43.

Which one of the following statements for a dc machine which is provided with inter pole winding (IW) as well as compensating winding (CW) is correct

A. Both IW and CW are connected in series with Armature winding
B. Both IW and CW are connected in parallel with Armature winding
C. IW connected in series but CW is connected in parallel with Armature winding
D. CW connected in series but IW is connected in parallel with Armature winding
Answer» B. Both IW and CW are connected in parallel with Armature winding
44.

The transfer function of a system is 10/(1+s) when operating as a unity feedback system, the steady state error to a step input will be

A. 0
B. 1/11
C. 10
D. Infinity
Answer» C. 10
45.

In a thyristor Latching current is ________ than Holding current

A. Equal
B. Less
C. Greater
D. None
Answer» D. None
46.

Which is the most suitable power device for high frequency ( more 100 kHz) switching application?

A. Power MOSFET
B. BJT
C. SCR
D. UJT
Answer» B. BJT
47.

Mho relay is usually employed for the protection of

A. Short lines only
B. Medium lines only
C. Long lines only
D. Any line
Answer» D. Any line
48.

In a synchronous alternator, the armature reaction is solely determined by

A. Power factor of the load
B. Amount of current drawn from the alternator
C. Speed of the prime mover driving the alternator
D. Excitation voltage
Answer» B. Amount of current drawn from the alternator
49.

The Function of Shunt in an Ammeter is

A. To bypass the current
B. To increase the Resistance of the meter
C. To decrease the voltage drop
D. To increase the current in the meter coil
Answer» B. To increase the Resistance of the meter