adventures of huckleberry finn essays

adventures of huckleberry finn essays The Adventures of Huckleberry Finn, a renowned novel by Mark Twain, is the story of a young boy, who, in a desperate attempt to escape his abusive and poverty stricken home, escapes and seeks help with the Mississippi River, where he experiences many different trials. The novel was finally published in 1885, being written on spurts of inspiration interrupted by long periods during which it sat on the authors desk. Now it is published in at least twenty-seven languages. Samuel Clemens, the name that lies under the pen name of Mark Twain, was born in Missouri in 1835. The town where he lived, Hannibal, Missouri, became the model for St. Petersburg, the fictional town of Huckleberry Finn. Missouri was a slave state during this period, and his family owned a few slaves, who worked as domestic servants rather than working on the large agricultural plantations as most slaves in the deep South did. The institution of slavery is prominent in the development of the themes and characters of the novel. Twain received a brief formal education before going to work as an apprentice in a print shop. He later found work on a steamboat in the Mississippi River where he took his pseudonym, Mark Twain, from the call a steamboat worker would make when the ship reached two fathoms. He eventually went to work as a journalist and then as a humorist. Twain is also known to have written The Gilded Age (1873), The Prince and the Pauper (1882), Life on the Mississippi (1883 ), and Tom Sawyer (1876). The Adventures of Huckleberry Finn outlines the different experiences and developing friendship of the novels two main characters, Huck and Jim. Huck, a young boy trying to escape from his life, and Jim, a black slave, wanting to escape from being sold to a farmer in the deep South, join together to sail on the Mississippi River to the Ohio River, which would lead to their freedom, but they miss it in the dark. Huck faces a moral dilemma ...

How Inverters and Converters Work in Hybrids and Electric Vehicles

How Inverters and Converters Work in Hybrids and Electric Vehicles In a hybrid and other electric vehicles (EVs), two key elements work together to manage power and recharge the circuits. Here is how these critical components- the inverter and converter- work in tandem.   The Function of an Inverter Broadly speaking, an inverter  is an electrical device that converts electricity derived from a DC (Direct Current) source to AC (Alternating Current) of the type that can be  used to drive a device or appliance. In a solar power system, for example, the power stored by batteries charged by solar panels is converted to standard AC power by the inverter, which provides the power to plug-in outlets and other standard 120-volt devices.   An inverter serves the same kind of function in a hybrid or EV car, and the theory of operation is relatively simple. DC power, from a hybrid battery, for example, is fed to the primary winding in a transformer within the inverter housing. Through an electronic switch (generally a set of semiconductor transistors), the direction of the flow of current is continuously and regularly flip-flopped (the electrical charge travels into the primary winding, then abruptly reverses and flows back out). The in/outflow of electricity produces AC current in the transformers secondary winding circuit. Ultimately, this induced alternating current electricity provides power for an AC load- for example, an electric vehicles (EV) electric traction motor. A rectifier is a similar device to an inverter except that it does the opposite, converting AC power to DC power. The Function of a Converter More properly called a voltage converter, this electrical device actually changes the voltage (either AC or DC) of an electrical power source. There are two types of voltage converters: step up converters (which increases voltage) and step down  converters (which decreases voltage). The most common use of a converter is to a take relatively low voltage source and step-it-up to high voltage for heavy-duty work in a high power consumption load, but they can also be used in reverse to reduce voltage for a light load source. Inverter/Converter Tandem Units An inverter/converter is, as the name implies, one single unit that houses both an inverter and a converter. These are the devices that are used by both EVs and hybrids to manage their electric drive systems. Along with a built-in charge controller, the inverter/converter supplies current to the battery pack for recharging during regenerative braking, and it also provides electricity to the motor/generator for vehicle propulsion. Both hybrids and EVs use relatively low-voltage DC batteries (about 210 volts)  to keep the physical size down, but they also generally use highly efficient high voltage (about 650 volts) AC motor/generators. The inverter/converter unit choreographs how these divergent voltages and current types work together. Because of the use of transformers and semiconductors (and the accompanying resistance encountered), enormous amounts of heat are emitted by these devices. Adequate cooling and ventilation are paramount to keeping the components operational. For this reason,  inverter/converter installations in hybrid vehicles have their own dedicated cooling systems, complete  with pumps and radiators, that are entirely independent of the engines cooling system.