Electrical Engi...

A parallel plate air capacitor as shown below has a total charge Q and a breakdown voltage V. A slab of a dielectric constant 6 is inserted as shown. The maximum breakdown voltage and the charge at this voltage respectively would be

For a n-variable Boolean logic expression, the minimum and maximum possible number of essential prime implicants are ______ and ______ respectively.

A 2 pole, 50 Hz single phase induction motor running at 2600 rpm has an effective rotor resistance and reactance each of 0.5 Ω. The stator impedance and magnetizing current are to be neglected. The frequencies of rotor current in forward branch and in backward branch are to be respectively

Let V_sc is the voltage required to circulate rated current on short circuit, θ_sc is the power factor angle on short circuit, and θ₂ is the load power factor angle and E₂ is the secondary rated voltage. The Per unit voltage regulation of a transformer is given by

A power system consists of 300 buses out of which 20 buses are connected with generators, 25 buses are the ones with controlled reactive power support and 15 buses are the ones with fixed shunt capacitors. All other buses are load buses. It is proposed to perform a load flow analysis using Newton-Rapson method. The size of the Newton-Rapson Jacobian matrix is

A network is described by the state model as

ẋ₁ = -2x₁ + x₂

ẋ₂ = x₁ – 3x₂ + u

y = 2x₁

The system is

A slip-ring induction motor is expected to be started by adding extra resistance in the rotor circuit. The benefit that is derived by adding extra resistance in the rotor circuit in comparison to the rotor being shorted is

At 50% of full load the armature current drawn by a dc shunt motor is 40 A when connected to a 200 V supply. By decreasing the field flux its speed is raised by 20%. This also causes a 10% increase in load torque. The armature resistance including the brushes is 1 ohm. Neglecting armature reaction and saturation the percentage change in field current will be