Bissoy.com
Doctors Medicines MCQs Q&A

Related Questions

A teacher asks students to suggest a method to demagnetise a magnet. Some responses are: A) "dropping a magnet on floor several times" B) "breaking the magnet into 2 halves" C) "heating the magnet" D) "throwing the magnet in water" E) "by hammering it" Which of the following are correct?
When is a ceramic magnet used as a permanent magnet in a permanent magnet DC motor?
Which of the following features of the Permanent Settlements of 1793 is/are correct? 1. The Permanent Settlements vested land ownership rights in the peasants 2. The Permanent Settlement vested land ownership rights in the Zamindars 3. The Zamindars had to pay a fixed amount of rent by a particular date 4. The Zamindars benefited hugely from the Permanent Settlement while the peasants suffered Select the correct answer using the code given below:
With reference to the properties of magnetism, consider the following statements: 1. A natural magnet is an oxide of iron. 2. When a magnet is freely suspended, its one pole is always directed towards the north. 3. The middle part of the magnet has maximum magnetic power. 4. Similar poles repel each other and dissimilar poles attract each other. Which of the statements given above is/are correct?
In the following question, sentences of a paragraph have been jumbled and labelled as A, B, C and D. You are required to rearrange the jumbled sentences of the paragraph and mark your response accordingly by selecting the correct option. A: An induction motor can, therefore, be made without electrical connections to the rotor. B: Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. C: An induction motor's rotor can be either wound type or squirrel-cage type. D: An induction motor or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding.
Permanent magnet DC motor is more expensive than an Induction motor.
In case of synchronous motor, which of the following are true? a. Synchronous motor is not self-starting b. If the rotor poles are excited by field current and the stator terminals are connected to AC supply, motor vibrates. c. Variable frequency supply is used to start synchronous motor. d. By using frequency converter, a synchronous motor can be brought from standstill to its desired speed.
Consider the following statements: In the above figure, the curves pertain to the DC motor A. Speed vs Armature current characteristic of a DC shunt motor B. Torque vs Armature current characteristic of a DC shunt motor C. Speed vs Armature current characteristic of a DC series motor D. Torque vs Armature current characteristic of a DC series motor
Which of the following statements are correct for dc shunt motor? 1. Speed of a shunt motor is sufficiently constant 2. For the same current input, its starting torque is not high as that of series motor 3. The motor can be directly coupled to a load such as fan whose torque increases with speed Select the correct answer using the code given below.
The rotor of a hysteresis motor is made of ceramic permanent magnet material, which causes: