Speedometer: An instrument which registers the speed of the vehicle
Telephone: A device by virtue of which two persons at two different places can communicate. It
consists of two main parts (i) a microphone and (ii) a receiver.
Telstar: It is a space communication satellite developed by Bell for overseas communications. It was
launched on July 10, 1962 from Cape Kennedy (U.S.A.). Telstar, in addition to telephone calls,
enables television microwave transmissions to be made from and to any country with a receiving and
transmitting station.
Telemeter: Is an apparatus for recording physical events happening at a distance.
Theodolite: An instrument for use in land surveying for measuring vertical and horizontal angles.
Thermometer: It is an instrument to measure the temperature.
Thermionic valve: Used in wireless telegraphy and radio broadcasting.
Thermostat: It is an instrument which controls temperature automatically. It is used in refrigerators,
air-conditionsers, geysers etc.
Transformer: It is an electric apparatus which is used to convert high voltage to low and vice versa.
Tachometer: An instrument for measuring the speed of aeroplanes, motors, etc.
Television: It is the transmission of images of moving objects by radio waves.
Telescope: An instrument designed to view the distant object easily.
Teleprinter: An instrument which prints automatically messages sent from one place to another on
telegraph lines.
Viscometer: Is an instrument to measure viscosity.
Voltmeter: It is an instrument to measure the potential difference across two points of an electrical
Voltameter: It is an apparatus for producing electrolysis in liquids
Wattmeter: It is an instrument for the direct measurement of power in watt of an electrical circuit.
Wavemeter: It is an instrument for measure the wavelength of a radiowave.