Electrical Engineering Gate 2014 Set-3 Questions with Answer

Ques 14 GATE 2014 SET-3

The torque-speed characteristics of motor (T_M) and load (T_L) for two cases are shown in the figures (a) and (b). The load torque is equal to motor torque at points P, Q, R and S

Ques 15 GATE 2014 SET-3

An open circuit test is performed on 50 Hz transformer, using variable frequency source and keeping V/f ratio constant, to separate its eddy current and hysteresis losses. The variation of core loss/frequency as function of frequency is shown in the figure

Ques 16 GATE 2014 SET-3

A non-salient pole synchronous generator having synchronous reactance of 0.8 pu is supplying 1 pu power to a unity power factor load at a terminal voltage of 1.1 pu. Neglecting the armature resistance, the angle of the voltage behind the synchronous reactance with respect to the angle of the terminal voltage in degrees is ________.

Ques 17 GATE 2014 SET-3

A separately excited 300 V DC shunt motor under no load runs at 900 rpm drawing an armature current of 2 A. The armature resistance is 0.5 Ω and leakage inductance is 0.01 H. When loaded, the armature current is 15 A. Then the speed in rpm is ________.

Ques 18 GATE 2014 SET-3

The parameters measured for a 220V/110V, 50 Hz, single-phase transformer are:
Self inductance of primary winding = 45 mH
Self inductance of secondary winding = 30 mH
Mutual inductance between primary and secondary windings = 20 mH
Using the above parameters, the leakage (L_l1, L_l2) and magnetizing (L_m) inductances as referred to primary side in the equivalent circuit respectively, are

Ques 19 GATE 2014 SET-3

An LPF wattmeter of power factor 0.2 is having three voltage settings 300 V, 150 V and 75 V, and two current settings 5 A and 10 A. The full scale reading is 150. If the wattmeter is used with 150 V voltage setting and 10 A current setting, the multiplying factor of the wattmeter is ________.

Ques 20 GATE 2014 SET-3

The two signals S1 and S2, shown in figure, are applied to Y and X deflection plates of an oscilloscope.

Ques 21 GATE 2014 SET-3

A hollow metallic sphere of radius r is kept at potential of 1 Volt. The total electric flux coming out of the concentric spherical surface of radius R(>r) is

Ques 22 GATE 2014 SET-3

A perfectly conducting metal plate is placed in x-y plane in a right handed coordinate system. A charge of +32πε_o√2 columbs is placed at coordinate (0, 0, 2). ε_o is the permittivity of free space. Assume î, ĵ, k̂ to be unit vectors along x, y and z axes respectively. At the coordinate (√2,√2,0), the electric field vector E (Newtons/Columb) will be

Ques 23 GATE 2014 SET-3

Two matrices A and B are given below:

Ques 24 GATE 2014 SET-3

A particle, starting from origin at t=0 s, is traveling along x-axis with velocity
v = (π/2)cos((π/2)t)m/s
At t = 3 s, the difference between the distance covered by the particle and the magnitude of displacement from the origin is ________.

Ques 25 GATE 2014 SET-3

Let ∇·(fv) = x²y+y²z+z²x, where f and v are scalar and vector fields respectively. If v = yi+zj+xk, then v·∇f is

Ques 26 GATE 2014 SET-3

Lifetime of an electric bulb is a random variable with density f(x)=kx², where x is measured in years. If the minimum and maximum lifetimes of bulb are 1 and 2 years respectively, then the value of k is ________.