Give two examples of photoelectric cells and explain how they work?

Answer 1

The most common photoelectric cells consist of two electrodes separated by light sensitive semiconductor material. A high voltage source, such as a battery, is connected to the electrodes set up a current even in the absence of light. When light strikes the semiconductor material in the photocell, current in the circuit increases in proportion to the intensity of the light.

The current from a photoelectric cell is often used to operate switches or relays, so are often used in automatic door openers and intrusion alarms. This type of photoelectric cells are called electric eyes.

Answer 2

1. Solar panels are a common example of photoelectric cells. They work by using semiconducting materials to convert sunlight into electricity through the photovoltaic effect.

2. Light sensors in cameras and smartphones are another example. When light hits the sensor, it generates electrical signals that are then converted into digital images.