Hygrometer: An apparatus for measuring the humidity of air.
Internal Combustion Engine: An engine in which heat energy added the air within the working
cylinder and converted into mechanical work through the medium of a piston or by a turbine rotator.
Lactometer: A typical hygrometer for testing pure milk.
Laser: A device to throw a thin beam of light that is carried over great distances.
Water Meter: For measuring gallons of water consumed.
Magneto: A part of the motor car that converts mechanical energy into electrical energy.
Manometer: For determining the pressure of a gas.
Micrometer: An instrument for measuring distance of angles.
Microphone: An instrument which intensifies and renders audibly the faintest possible sound.
Microscope: An optical instrument for producing greatly magnified images of very small objects.
Periscope: Optical instrument used in trench warfare and in submarines for enabling an observer to
see surrounding objects from a lower level.
Phonograph: Is an instrument used for reproducing sound.
Photometer: Is an apparatus used to compare the illuminating power of two sources of light.
Pipette: It is a glass tube with the aid of which a definite volume of liquid may be transferred.
Pyrometer: Is an instrument for measuring high temperatures.
Radar: An instrument to detect the presence of enemy aircraft, submarine, etc., and also to determine
its direction, distance and speed.
Radiogram: A combined radio and gramophone.
Refract meter: It is an instrument to measure refractive indices.
Radiometer: An instrument for measuring the radiant energy of light and heat.
Samaphore: System of signalling between two places generally ships.
Seismometer: It is an apparatus for measuring the origin of earthquakes.
Sextant: An instrument for measuring angle.
Spark Plug: Device for producing an electric spark to set off combustion in the cylinder of a petrol
engine.
Stethoscope: A doctor"s tool to listen to the beat of the heart.
Stereoscope: A binocular optical instrument through which a double Photograph taken from two
slightly different angles by two lensed cameras is viewed.
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