![]() Before 2019, the ampere was defined formally as the constant current at which a force of 2 × 10 -7 newtons per meter length would be produced between two conductors, where the conductors are parallel, have infinite length, are placed in a vacuum, and have negligible circular cross-sections. The size of the unit was chosen such that it would fit conveniently within the metre-kilogram-second system of units. In the centimeter-gram-second system of units, the ampere was defined as one tenth of the unit of electrical current of the time, which is now known as the abampere. History/origin: The ampere is named after Andre-Marie Ampere, a French mathematician and physicist. This definition is effective since 2019, and is a significant change from the previous definition of the ampere. The second is defined based on the cesium frequency, Δ νCs. The ampere is defined formally based on a fixed value for the elementary charge, e, of 1.602176634 × 10 -19 when expressed in the unit C, which is equal to A Ampereĭefinition: The ampere (symbol: A), often referred to as simply amp, is the base unit of electric current in the International System of Units (SI). ![]() There are many devices that measure units in terms of milliamperes such as galvanometers and ammeters, though these devices do not exclusively measure milliamperes. The ampere can be preceded by any of the metric prefixes in order to report units in the desired magnitude.Ĭurrent use: As a submultiple of an SI unit, the milliampere is used worldwide, often for smaller measurements of electrical current. ![]() The prefix "milli" indicates one thousandth of the base unit it precedes, in this case the ampere. History/origin: The milliampere has its origins in the ampere. It is defined as one thousandth of an ampere. People were searching for bodies and men in a rubber boat retrieved one from the sea, footage broadcast by Libyan TV station al Masar showed.Definition: A milliampere (symbol: mA) is a submultiple of the SI base unit of electrical current, the ampere. Karim al Obaidi, a passenger on a plane from Tripoli to the east, said he has "never felt as frightened" and that he has lost contact with family. Her brother-in-law, Walid Abdulati, said "we are not speaking about one or two people dead, but up to 10 members of each family dead". It may be days before we know the true extent of this disaster and they get the help they need.Īt Tripoli airport in northwest Libya, one woman broke down in tears as she found out most of her family were dead or missing. There are signs of aid moving from the capital eastwards, but for people in the flooded areas it cannot come quick enough. There are reports entire communities have been washed away into the sea.Īny relief effort will be also complicated by the political divisions that exist.Īn internationally recognised government sits in the capital Tripoli but the east is administered - where Derna is located - by a different authority. Reaching the areas worst affected is not easy - the swollen rivers and intense flash flooding have swept away roads and homes. We don't really know the numbers of dead - it's definitely in the thousands but that tragic figure could rise much higher.Īid agencies are pointing to the collapse of two dams in the coastal city of Derna as the reason for the worst of the devastation.Īt least 10,000 people are missing according to the Red Crescent. The disaster has been compounded by the problems Libya is already facing - years of war since Muammar Gaddafi was ousted have left the fractured nation in no place to deal with this terrible climatic event. Storm Daniel has already caused chaos in southern Europe but the flooding in the east of the country may be even worse. International correspondent has taken time but it's now quickly becoming clear to the outside world that Libya is facing a significant humanitarian catastrophe.
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