why does the remote control of a televesion does not function if covered by an aluminum foil
The remote control of a television does not function when covered by aluminum foil because aluminum foil is electrically conductive. When you press a button on the remote control, it sends out infrared signals that are received by a sensor on the television. However, when the remote control is covered with aluminum foil, the foil acts as a barrier and prevents the infrared signals from reaching the sensor.
To understand this concept, we need to know that infrared signals are a form of electromagnetic radiation that are used for remote control communication. These signals are emitted by an infrared LED (Light Emitting Diode) present in the remote control and are reflected by the surrounding objects towards the sensor on the television.
When the remote control is not covered, the infrared signals emitted by the LED can freely travel and be received by the sensor on the television. However, when the remote control is covered with aluminum foil, the foil reflects and absorbs the infrared signals, preventing them from reaching the sensor.
So, when you press the buttons on the remote control, the television does not respond because the infrared signals are being blocked by the aluminum foil. Removing the foil allows the infrared signals to travel unobstructed and enables the remote control to function properly again.