Rajasthan Technical Education Second Year Paper 2016 Electrical Engineering

Rajasthan Technical Education Second Year Paper 2016 Electrical Engineering

As the load increases, the speed of a d.c. shunt motor
(a) increases proportionately
(b) remains constant
(c) increases slightly
(d) reduces slightly

The speed of a d.c. motor can be controlled by varying
(a) its flux per pole
(b) resistance of armature circuit
(c) applied voltage
(d) All of the above

An ideal transformer is one which has
(a) A common core for its primary and secondary winding.
(b) No losses and magnetic leakage.
(c) Core of stainless steel and windings of pure copper wires.
(d) Interleaved primary and secondary windings.

A step-up transformer increases
(a) voltage
(b) current
(c) power
(d) frequency

Transformers are rated in KVA instead of kW because
(a) Load power factor is often not known
(b) KVA is fixed whereas kW depends on load power factor
(c) Total transformer loss depends on volt-ampere
(d) All above are correct

The main purpose of performing open-circuti test on a transformer is to measure its
(a) Copper loss
(b) Core loss
(c) Total loss
(d) Insulation resistance

The principle of operation of a 3-phase induction motor is most similar to that of a
(a) Sychrounous motor
(b) Repulsion-start induction motor
(c) Transformer with a shorted secondary
(d) Capacitor start induction-run motor

In a 3 phase induction motor the slip speed is
(a) Ns/N
(b) Ns+N
(c) Ns-N
(d) N – Ns

The speed of rotor of an induction motor is always __________synchronous speed.
(a) equal to
(b) more than
(c) less than
(d) half of

A single phase induction motor is
(a) self starting
(b) not self starting
(c) self starting with the help of auxiliary winding
(d) None of the above

For cranes, the motor used must have
(a) Low starting torque
(b) Constant speed
(c) High starting torque
(d) None of the above

Motor used in lathe machine must have
(a) High starting torque
(b) Low starting torque
(c) Constant speed
(d) None of these

Which of the following motor is used in rolling mill ?
(a) Squirrel cage induction motor
(b) Single phase induction motor
(c) D.C motor
(d) Slipring induction motor

In resistance heating the material of element is
(a) Steel
(b) Copper
(c) Nichrome
(d) Aluminium

In induction heating, which of the following is of high value ?
(a) Current
(b) Frequency
(c) Voltage
(d) Power factor

Lumen is the unit of
(a) Illumination
(b) Luminous Flux
(c) Intensity
(d) Solid angle

Law of illumination is
(a) Inverse square law
(b) Lambert’s cosine law
(c) Cosine cube law
(d) All of the above