A centimetre (international spelling as used by the International Bureau of Weights and Measures; symbol cm) or centimeter (American spelling) is a unit of length in the metric system, equal to one hundredth of a metre, centi being the SI prefix for a factor of 1/100. The centimetre was the base unit of length in the now deprecated centimetre–gram–second (CGS) system of units. Though for many physical quantities, SI prefixes for factors of 103—like milli- and kilo-—are often preferred by technicians, the centimetre remains a practical unit of length for many everyday measurements. A centimetre is approximately the width of the fingernail of an average adult person
Here is the P-type metal-oxide-semiconductor logic uses p-channel metal-oxide-semiconductor field effect transistors (MOSFETs) to implement logic gates and other digital circuits. PMOS transistors operate by creating an inversion layer in an n-type transistor body. This inversion layer, called the p-channel, can conduct holes between p-type "source" and "drain" terminals.
Arduino is an open-source hardware and software company, project and user community that designs and manufactures single-board microcontrollers and microcontroller kits for building digital devices.
An electric current is the rate of flow of electric charge past a point:2:622 or region.:614 An electric current is said to exist when there is a net flow of electric charge through a region.:832 In electric circuits this charge is often carried by electrons moving through a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in an ionized gas (plasma). The SI unit of electric current is the ampere , which is the flow of electric charge across a surface at the rate of one coulomb per second. The ampere (symbol: A) is an SI base unit:15 Electric current is measured using a device called an ammeter.
When a bunch of electrons congregate in one place, their combined charges build up to a certain level of electric potential energy in that object. For example, when I rub this rubber balloon on my wool scarf, it causes a bunch of the electrons from the scarf to jump over on the balloon. Now the balloon is negatively charged, because it has a surplus of negatively charged electrons, and the scarf is positively charged, because it has a shortage of electrons.