Question

Check your smart phone and find some electric/magnetic components, explain their working principle from physics. Such as touch screen, camera, flashlight, speaker, recorder, radio etc. Must list more than 4 components.

( not hand writting )

Answer 1

Speaker : The basic principle of this component is that it converts electrical signal into sound signal by vibrations in the membranes present on the surface of the speakers by using principles of electromagnetism. A coil of copper wire attached to this membrane moves in a permanent magnetic field created by a circular magnet. The electrical signals moving inside the coil lead to up and down motion of the membrane thus creating sounds.

Microphone: This one is opposite to that of the speaker as here the vibrations of the membrane create electrical signals that in turn are stored or used for communication. The construction of the microphone is quite similar to that the of the speaker and the output given by this component is very low in terms of intensity and hence needs to be amplified.

Microprocessor or SoC : SoC stands for system on a chip. This is basically the heart and brains of the smartphone and this CPU performs and handles all major operations inside the smartphones. This is basically a tiny wafer of silicon with an immense amount of transistors and diodes present on it. These devices allow this chip to perform logical operations such as in logic gates.

Flashlight: It is simply an LED that emit light due to the excitation and dexcitation of electrons in the forbidden zone of the diode junction. This excitation is performed by making use of biasing property of the diodes and the neccessary energy is supplied by using the battery of the device.

Battery: This component is used to store charge carriers and hence charge to provide potential difference to all the other components and device for operation. This can thought of as the power house for the whole device. As this is the sole power supply in smartphones generally and without it we can't even turn the phone on.