What is a photocell GCSE?
What is a photocell GCSE?
A photocell changes light into electricity. A solar cell is a photocell that uses light from the Sun. The current (or power) output from a photocell depends on the area exposed to the light. A larger area produces a greater current. Photocells can be used in places where mains electricity is not easily available.
What is photocell and its principle?
The photocell is a device that works on the principle of the photoelectric effect. A photocell converts light energy to electric energy. The photons with suitable frequency will remove electrons from the metal surface.
What is a photocell in physics?
photoelectric cell, also called Electric Eye, Photocell, or Phototube, an electron tube with a photosensitive cathode that emits electrons when illuminated and an anode for collecting the emitted electrons.
What is the advantage of using photocell?
P2 Advantages and Disadvantages of Photocells
| P2 Advantages and Disadvantages of Photocells | |
| Advantages No fuel is needed No power cables are needed They have a long life and are rugged Renewable energy resource Do not produce polluting waste | Disadvantages No power in bad weather No power at night Little maintenance |
How does a photocell generate electricity?
When light photons fall on it, they force electrons to leap out of it and these are promptly attracted to the positive terminal, which collects them and channels them into a circuit, producing electric power. This basic design is called a photoemissive cell or phototube.
What are characteristics of photocell?
Photo-Emissive Cell: There are two types of photo-emissive cells; Vacuum type or gas filled type cells. Generally, it consists of two electrodes i.e. cathode (K) and anode (A). The cathode is in the form of semi-cylindrical plate coated with photo-sensitive material like sodium potassium or cesium i.e. alkali metals.
How does a photo eye work?
A Photoelectric Sensor consists primarily of an Emitter for emitting light and a Receiver for receiving light. When emitted light is interrupted or reflected by the sensing object, it changes the amount of light that arrives at the Receiver. The Receiver detects this change and converts it to an electrical output.
When should I use photocell?
Photocells are used in automatic lights to activate whenever it gets dark, and the activation/deactivation of streetlights mainly depends on the day whether it is day or night. These are used as timers in a running race to calculate the runner’s speed. Photocells are used to count the vehicles on the road.
Does photocell converts light energy into electrical energy?
A photo cell (or solar cell) is an electric device that converts energy of light directly into electrical energy (electricity) by the photovoltaic effect, which is a physical and chemical phenomenon.
Where is photocell located?
For most general applications the photocell should be mounted between 6-8 feet of the window area, central to the area illuminated by the electrical lighting that will be controlled. In all cases the photocell must be mounted so that it looks at reflected light only and not at any direct light.
