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प्रश्न
State two ways to increase the speed of rotation of a D.C. motor.
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उत्तर
By increasing the magnetic flux [by using strong magnet]
By reducing number of turns in the winding.
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संबंधित प्रश्न
State the rule to determine the direction of a force experienced by a current-carrying straight conductor placed in a magnetic field which is perpendicular to it.
Name and state the rule to determine the direction of magnetic field around a straight current-carrying conductor.
List three ways in which the magnetic field strength of a current-carrying solenoid can be increased?
The magnetic field lines in the middle of the current-carrying solenoid are?
(a) circles
(b) spirals
(c) parallel to the axis of the tube
(d) perpendicular to the axis of the tube
A current-carrying conductor is held in exactly vertical direction. In order to produce a clockwise magnetic field around the conductor, the current should passed in the conductor:
(a) from top towards bottom
(b) from left towards right
(c) from bottom towards top
(d) from right towards left
A current-carrying conductor is placed perpendicularly in a magnetic field. Name the rule which can be used to find the direction of force acting on the conductor.
In the simple electric motor of figure given below, the coil rotates anticlockwise as seen by the eye from the position X when current flows in the coil
Is the current flowing clockwise or anticlockwise around the coil when viewed from above?
State Fleming’s left-hand rule.
The following diagram shows two parallel straight conductors carrying the same current. Copy the diagram and draw the pattern of the magnetic field lines around them showing their directions. What is the magnitude of the magnetic field at a point 'X' which is equidistant from the conductors? Give justification for your answer.
When current is parallel to a magnetic field, then force experience by the current-carrying conductor placed in a uniform magnetic field is ____________.
