An incandescent light bulb, incandescent lamp or incandescent light globe is an electric
light with a wire filament heated to such a high temperature that it glows with visible.
light (incandescence).
The filament, heated by passing an electric current through it, is protected from.
oxidation with a glass or fused quartz bulb that is filled with inert gas or evacuated. In
a halogen lamp, filament evaporation is slowed by a chemical process that redeposits.
metal vapor onto the filament, extending its life.
A cash register, also referred to as a till in the United Kingdom and other
Commonwealth countries, is a mechanical or electronic device for registering and
calculating transactions at a point of sale. It is usually attached to a drawer for storing
cash and other valuables. The cash register is also usually attached to a printer, that can.
print out receipts for record keeping purposes.
A thermostat is a component which senses the temperature of a system so that the
system’s temperature is maintained near a desired setpoint.
A thermostat can often be the main control unit for a heating or cooling system, in
applications ranging from ambient air control to such as automotive coolant control,
but is also used in many other applications, such as an electric clothes iron.
It is a “closed loop” control device, as it seeks to reduce the error between the desired
and measured temperatures. Sometimes a thermostat combines both the sensing and
control action elements of a controlled system, such as in an automotive thermostat.
The word thermostat is derived from the Greek words thermos, “hot” and stators,
“Standing, stationary”.
A steam turbine is a device that extracts thermal energy from pressurized steam and
uses it to do mechanical work on a rotating output shaft. Its modern manifestation was
invented by Sir Charles Parsons in 1884.
Lesson Learning 