AMIE Study Circle Blog

(A) Choose the correct answer: 2 x 5 1. The transfer function of a system is G(s) = 10/(1 + s). The steady-state error to unit step input when operated at unity feedback system is  (a) 10  (b) 0 (c) 1/11 (d) 10 2. Sphere gaps are used for the measurement of  (a) Instantaneous values of voltage (b) r.m.s. values of voltage (c) Peak values of voltage (d) Overage values of voltage 3.  The inductance of low Q can be measured by using (a) Schering Bridge (b) Anderson’s Bridge (c) Hay’s Bridge (d) De Sauty’s Bridge 4. An average responding rectifier type electronic ac voltmeter has its scale calibrated in terms of the RMS value of a sine wave. If a square wave voltage of peak amplitude of 100 V is measured using this voltmeter, what will be the reading indicated by the meter? (a) 200V (b) 100 V (c) 111 V (d) 100√2V 5. The given block diagram is equivalent to (a)  (b)  (c)  (d)  Answers 1. (c)  2. (c) a spark gap can be used for measurement of the peak value of the voltage if the gap distan

Short answer type (2 x 4) Find the dimension of Torque in the SI unit of the M, L, T, I system. Dimension formula of torque = dimension formula of force X dimension formula of length [MLT -2 ][L]=[ML 2 T -2 ] Find the equivalent resistance of series connected two resistances R₁ = 40 ± 2% and R₂ = 60 ± 3%. R 1  + R 2  = 40 ± 2 + 60 ± 3 = 100 ±5% Write the type and order of a system whose transfer function is given by Order of the system can be defined as the value of the highest exponent that appears in the denominator of the transfer function. (Total number of poles). In the given expression highest exponent is 3. Hence the order of the system is 3. Find the no. of significant figures in  (a) 0.0012 (b) 12.00 (c) 1200 (d) 12 0.0012 has 2 significant figures. 12.00 has 4 significant figures. 1200 has 2 significant figures.  12 has 2 significant figures.  Significant figures are the digits of a number that are meaningful in terms of accuracy or precision. They include: Any non-zero digit

Answer the following in brief (2x10) What do you understand by magnetic potential and how it is measured? the scalar quantity characteristic of a point in a magnetic field whose negative gradient equals the intensity or strength of the magnetic field and which represents the work required to bring a unit north pole from a point infinitely remote up to the point in question A tangent galvanometer is an absolute instrument, justify your answer. Absolute instruments provide the quantity to be measured in terms of the instrument constant and its deflection. For example, a tangent galvanometer gives the value of the current to be measured in terms of the tangent of the angle of deflection produced, the horizontal component of the earth’s magnetic field, the radius, and the number of turns of the wire used. Such instruments are used in laboratories and in similar institutions as standardizing instruments. Write the restoring torque equation for the gravity control instrument. When the coil i

Describe the following in brief: Local attraction The North end of a freely suspended magnetic needle always points to the magnetic north, if it is not influenced by any other external forces except the earth’s magnetic field. It is a common experience that the magnetic needle gets deflected from its normal position if placed near magnetic rocks, iron ores, cables carrying current or iron electric poles.  Such a disturbing force is known as ‘Local attraction’. Magnetic bearings are, therefore, not reliable unless these are checked against the presence of local attractions at each station and their elimination. Sensitivity of the bubble Sensitiveness of Level Tube Sensitivity of a level tube depends upon the following: The radius of curvature of the internal surface: Larger the radius, the greater is the sensitiveness. Diameter of the level tube: Larger the diameter, the greater is the sensitiveness. Length of the vapour bubble: Larger the length, the greater is the sensitiveness. Visco

Differentiate between the following (2 x 10) Systematic errors and Accidental errors Systematic errors  These are the errors that occur from well-understood causes and can be reduced by adopting suitable methods. For example, the error due to the sag of a tape supported at the ends can be calculated and subtracted from each measurement. However, the tape can be supported throughout its length at short intervals and the sag error may be reduced to a negligible quantity. It always has the same magnitude and signs so long as the conditions remain the same and such an error is called constant systematic error. Whereas, if the conditions change, the magnitude of the error changes and this is known as variable systematic error. A systematic error follows a definite mathematical or physical law and, therefore, a correction can always be determined and applied. lt| is also known as cumulative error. Accidental errors  These are errors due to a combination of causes and are beyond the control o

Differentiate between the following (2x10) Fore bearing and Back bearing Fore Bearing (F.B.) The bearing of a line in the direction of progress of the survey is called the fore or forward bearing. Back Bearing (B.B.) The bearing of a line in the opposite direction of progress of the survey is known as back or reverse bearing. The bearing of a line is indicated in the order in which the line is lettered. Thus, the bearing from A to B is α the fore bearing a of the line AB. whereas the bearing of line AB in the direction B to A is its back bearing β. Triangulation and Trilateration Triangulation  When the area to be surveyed is of a considerable extent, triangulation is adopted. The entire area is divided into a network of triangles. Anyone side of any of the triangles so formed, is selected and is measured precisely. Such a line is called a baseline. All the angles in the network are measured with a transit. The lengths of the sides of all the triangles are then computed, from the measu

Differentiate between the following ( 2 x 10) Chain line and check line. Check Lines.   The line which is run in the field to check the accuracy of the fieldwork is called the check line. If the measured length of a check line agrees with the length scaled off the plan, the survey is accurate. Each triangle is generally provided with a check line. The check lines may be laid in such a way that a maximum number of details are intersected by it. Check lines may also be laid by joining the apex of the main triangle to any point on the opposite side or by joining two points on any two sides of the triangle. Vernier scale and the chord scale Vernier Scale  A device used for measuring the fractional part of one of the smallest divisions of a graduated scale. It usually consists of a small auxiliary scale that slides alongside the main scale.  The least count of the vernier = the difference between the smallest division on the main division and the smallest division on the vernier scale. Cho