When one end of a bar magnet is placed near a tv screen, the picture becomes distorted.
Why?
When a bar magnet is placed near a TV screen, the picture becomes distorted because the TV screen is typically made up of phosphor dots that emit light when struck by electrons. The process of generating images on a TV screen involves a beam of electrons moving back and forth across the screen, hitting the phosphor dots to create the different colors and shapes.
Now, in the presence of a magnet, the magnetic field of the magnet can interfere with the beam of electrons. This interference causes the path of the electrons to deviate or change, resulting in an altered and distorted picture on the screen.
To understand why the magnetic field affects the electron beam, we need to consider the properties of the bar magnet and the interaction between magnetic fields and moving charges.
The bar magnet has a north pole and a south pole, which generate magnetic fields. These magnetic fields have an influence on charged particles like electrons. When the magnet is brought near the TV screen, the magnetic field from the magnet interacts with the magnetic field generated by the electron beam.
The interaction between the magnetic fields causes the electron beam to experience a force, known as the Lorentz force, which acts perpendicular to both the direction of the electron beam and the magnetic field. As a result, the electron beam is deflected from its intended path, leading to distortions in the TV picture.
In summary, the distortion of the TV picture when a bar magnet is placed near the screen occurs due to the interaction between the magnetic field of the magnet and the electron beam. The Lorentz force caused by this interaction deflects the electron beam, resulting in the distorted picture on the screen.