Points to remember -Class 10 -Science- Physics-Chapter13: Magnetic Effects Of Electric Current

Class 10 -Science-Points to remember – Physics-Chapter13: Magnetic Effects Of Electric Current

Points to remember

A freely suspended magnet always stays north–south. 

◆ The region around a magnet in which its magnetic force can be detected is called the magnetic field. 

◆ Magnetic field is represented by magnetic field lines. 

◆ The tangent at any point of a magnetic field line represents the direction of magnetic field at the point. 

◆ The number of lines of force passing through a unit area represents the strength of the field. If the lines of force are closer, the magnetic field is stronger. 

◆ The magnetic field lines around a current carrying straight conductor are concentric circle around the conductor. 

◆ The direction of magnetic field due to a current–carrying straight conductor is given by Fleming’s right–hand rule. 

◆ The magnetic field due to a current–carrying solenoid is similar to that of a bar magnet. The magnetic field inside a solenoid is nearly uniform and is parallel to the axis of the solenoid. 

◆ A magnet formed due to the magnetic field of a current is called an electromagnet. An electromagnet essentially consists of a soft iron core wrapped around with an insulated copper wire coil. 

◆ An electric motor is a device that converts electrical energy into mechanical energy. It is based on the principle that : When a current carrying coil is placed in a magnetic field, a torque acts on it. 

◆ When a conductor moves perpendicular to a magnetic field, an emf is induced across its ends. The direction of induced emf or the induced current is determined by the Fleming’s right–hand rule. 

◆ Generator is based on the principle of electromagnetic field, with a continuous change in flux due to which an emf is induced. 

◆ Power is transmitted from the power station to cities at high voltage and low current to minimize power loss.

◆ A fuse is a wire of high resistance and made up of a material of low melting point.