Electric field

An electric field surrounds an electric charge, exerts force on other charges in the field, attracting or repelling them. Electric field is sometimes abbreviated as E-field; the electric field is defined mathematically as a vector field that associates to each point in space the force per unit of charge exerted on an infinitesimal positive test charge at rest at that point. The SI unit for electric field strength is volt per meter. Newtons per coulomb is used as a unit of electric field strength. Electric fields are created by time-varying magnetic fields. Electric fields are important in many areas of physics, are exploited in electrical technology. On an atomic scale, the electric field is responsible for the attractive force between the atomic nucleus and electrons that holds atoms together, the forces between atoms that cause chemical bonding. Electric fields and magnetic fields are both manifestations of the electromagnetic force, one of the four fundamental forces of nature. From Coulomb's law a particle with electric charge q 1 at position x 1 exerts a force on a particle with charge q 0 at position x 0 of F = 1 4 π ε 0 q 1 q 0 2 r ^ 1, 0 where r 1, 0 is the unit vector in the direction from point x 1 to point x 0, ε0 is the electric constant in C2 m−2 N−1When the charges q 0 and q 1 have the same sign this force is positive, directed away from the other charge, indicating the particles repel each other.

When the charges have unlike signs the force is negative, indicating the particles attract. To make it easy to calculate the Coulomb force on any charge at position x 0 this expression can be divided by q 0, leaving an expression that only depends on the other charge E = F q 0 = 1 4 π ε 0 q 1 2 r ^ 1, 0 This is the electric field at point x 0 due to the point charge q 1. Since this formula gives the electric field magnitude and direction at any point x 0 in space it defines a vector field. From the above formula it can be seen that the electric field due to a point charge is everywhere directed away from the charge if it is positive, toward the charge if it is negative, its magnitude decreases with the inverse square of the distance from the charge. If there are multiple charges, the resultant Coulomb force on a charge can be found by summing the vectors of the forces due to each charge; this shows the electric field obeys the superposition principle: the total electric field at a point due to a collection of charges is just equal to the vector sum of the electric fields at that point due to the individual charges.

E = E 1 + E 2 + E 3 + ⋯ = 1 4 π ε 0 q 1 2 r ^ 1 + 1 4 π ε 0 q 2 ( x 2 −

1931 Monaco Grand Prix

The 1931 Monaco Grand Prix was a Grand Prix motor race held at the Circuit de Monaco on 19 April 1931. With 16 Bugattis in a field of 23 cars, the event was close to being a single-make race. Among the 16 were four factory-team Type 51s driven by the Monegasque Louis Chiron, the Italian Achille Varzi and the French Albert Divo and Guy Bouriat; the real challenge came from the Maserati 8C 2500's driven by René Dreyfus, the Italian Luigi Fagioli and Clemente Bondietti. Rudolf Caracciola with his huge Mercedes SSKL was uncompetitive as his larger car performed poorly around the tight Monaco track; the race was between the red ones from Modena. When the start flag dropped it was Rene Dreyfus in his red Maserati who led into St. Devote, only to be passed by'Williams' on the hill to the Casino, but his lead was short lived as the Brit was sidelined by a broken valve spring, his race was over. Achille Varzi and Caracciola started closing on Dreyfus and Varzi managed to overtake the Frenchman on the 7th lap.

Caracciola struggled with a slipping clutch that gave in on lap 53. Starting Louis Chiron displayed his talents, he left them behind. Chiron, a native of Monaco, finished the race some 5 minutes ahead of Luigi Fagioli. Jean Bugatti could not control his joy and jumped over the parapet of the bleachers and fell into Louis Chiron's arms. For the Monegasque, this Monaco Grand Prix victory confirmed his reputation. Note: grid slots were determined by drawing lots

Hex (Poison Girls album)

Hex is the debut studio album by English anarcho-punk band Poison Girls, released in 1979 by record label Small Wonder. Words and music by the Poison Girls "Old Tarts Song"– 2:21 "Crisis"– 3:26 "Idealogically Unsound"– 2:40 "Bremen Song"– 7:15 "Political Love"– 2:31 "Jump Mama Jump"– 3:03 "Under the Doctor"– 2:49 "Reality Attack"– 5:25 Poison GirlsVi Subversa - guitar, vocals Richard Famous - guitar, vocals Bernhardt Rebours - bass Lance D'Boyle - drumswith: Eve Libertine - additional vocalsTechnicalJohn Loder - sound engineer Bernhardt Rebours - sleeve design Hex at Discogs