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The area around a magnet, in which its influence (force of attraction or repulsion) can be felt, is called its
The region around a magnet, in which its influence can be felt, is called its magnetic field
A constant current I flows through a horizontal metal wire in the plane of the paper from east to west as shown in the figure. The direction of magnetic field will be from north to south at a point :
Let a constant current I flows through a horizontal wire from east to west. The direction of magnetic field, as per right-hand thumb rule, will be from north to south at a point directly below the current-carrying wire.
What is that instrument which can detect the presence of electric current in a circuit?
The direction of magnetic field developed around a current-carrying conductor can be easily found by the use of
The direction of magnetic field developed around a current-carrying conductor can be found by the use of right-hand thumb rule.
The strength of the magnetic field around a current-carrying straight conductor
The strength of the magnetic field around a current-carrying straight conductor is directly proportional to the amount of current flowing in the conductor.
The strength of a magnetic field inside a long current-carrying straight solenoid coil is
The strength of a magnetic field inside a long, current-carrying, straight solenoid is uniform at all points. Moreover, the field depends on the amount of current flowing and the number of turns in solenoid coil besides its length
The most important safety method used for protecting home appliances from short circuiting or overloading is
It is most important method for protecting the electrical devices from short circuiting or overloading by stopping the flow of any large electric current exceeds from its rating.
An electron moves with a speed v along positive direction of x-axis. If a magnetic field B acts along the positive y-direction, then the force on the electron will act along
-ve z axis
We use left hand rule or right hand palm rule or cockscrew rule
as electron moves in positive x axis the current I is in -ve x axis
B is in +ve y axis
then -ve z axis is the direction of lorentz force
or u can just use vector cross product [-i x j ] = -k
To convert an AC generator into DC generator
To connect AC generator into DC generator, split ring type commutation must be used to get a unidirectional direct current.
The strength of magnetic field along the axis of a solenoid coil :
The strength of magnetic field along the axis of a solenoid coil increases on increasing the current flowing through the solenoid coil and on increasing the number of turns in the solenoid coil. Moreover, if a soft iron core is inserted inside the solenoid coil then magnetic field increases many fold.
The strength of magnetic field inside a long current carrying straight solenoid is
A current carrying solenoid produces a uniform magnetic field inside it.
A current-carrying conductor is placed perpendicular to the direction of a uniform magnetic field. The direction of force acting on the conductor due to magnetic field is given by
When a current-carrying straight conductor is placed perpendicular to the direction of a uniform magnetic field, it experiences a mechanical force. The direction of mechanical force is given by Fleming’s left-hand rule.
Commercial electric motors do not use
Using electromagnet, the magnetic field strength further increase by increasing the current. Hence it will enhance the power of electric.
A uniform magnetic field exists in the plane of paper Electron Proton pointing from left to right as shown in the figure. In the field an electron and a proton move as shown. The electron and proton experience
On applying Fleming’s left-hand rule we find that both electron as well as proton experience forces pointing into the plane of paper.
For a current in a long straight solenoid N-pole and S-poIe are created at the two ends. Among the following statements, the incorrect statement is
A solenoid behaves like a bar magnet. Hence the pattern of magnetic field associated with solenoid and around the bar magnet is same.
Choose the wrong statement out of the following :
Like magnetic poles (say N- and N-poles) always repel each other.
If the key in the given arrangement is taken out (the circuit is made open) and magnetic field lines are drawn over the horizontal plane ABCD, the lines are
Magnetic field lines around a straight current carrying conductor are in the form of concentric circle.