When we talk about the third rail, we mean the live rail which provides electric power to a train through a conductor placed alongside the rails.
Why is South London third rail?
The southern railway lines were electrified earlier than those in the north, and the third rail system was chosen due to its simplicity and cost-effectiveness.
What does third rail mean slang?
If you refer to something as the third rail of a political situation, you mean that it would be dangerous to make changes to that thing because people feel very strongly about it. [US] Politicians speak of Social Security as the third rail. To touch it is to commit political suicide.
Why does the UK use third rail?
Why is third rail slower?
Because of mechanical limitations on the contact to the third rail, trains that use this method of power supply achieve lower speeds than those using overhead electric wires and a pantograph. Nevertheless, they may be preferred inside cities as there is no need for very high speed and they cause less visual pollution.
Why does the London Underground use 4th rail?
The four rail system was first used in the early twentieth century. The isolated traction current return allowed a train's position to be detected using DC track circuits, and reduced any earth leakage currents that could affect service pipes, telephone cables, or cast iron tunnel liners.
Why does London Underground have 4 rails?
The four rail system was first used in the early twentieth century. The isolated traction current return allowed a train's position to be detected using DC track circuits, and reduced any earth leakage currents that could affect service pipes, telephone cables, or cast iron tunnel liners.
Does NYC have a third rail?
The third rail on subway tracks in New York City is an electrified rail that supplies power to the trains. It carries a high voltage of around 600-750 volts of direct current (DC) electricity.