Advertisements
Advertisements
Question
State the principle of a D. C. motor.
Advertisements
Solution
It is based on the principle that when an electric current is passed through a conductor placed normally in a magnetic field, a force acts on the conductor as a result of which the conductor begins to move. The direction of the force is obtained with the help of Fleming’s left hand rule.
RELATED QUESTIONS
Tick the most appropriate answer.
Which of the following methods is used to magnetize a magnetic without touching it by a magnet?
Show with the aid of a diagram how a wire is wound on a U-shaped piece of soft iron in order to make it an electromagnet. Complete the circuit diagram and label the poles of the electromagnet.
Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
Electric bell ______.
State the two properties of the magnetic lines of force around a circular coil.
A straight wire is held vertical and current is passed in it in the upward direction. A compass needle is kept near the wire in north of it. How is the needle deflected? What is the change in the deflection of the needle if the current in wire is reversed?
A straight current-carrying conductor is kept in a magnetic field. It Experiences a force. State three factors on which the magnitude of force Experienced by the conductor depends. Under what condition will the conductor Experience no force?
How does a magnetic field set up by a solenoid change when a soft iron core is inserted inside solenoid?
How does a magnetic field set up by a solenoid change when strength of current in the solenoid is decreased?
Which magnet will you use?
Iron is to be separated from trash.
Write the answer in your words.
How is an electromagnet made?
