scientist, discoveries & inventions MCQ section 1 MCQ Questions & Answers Detailed Explanation

Answer: (a)

Radar is an object detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain.

The radar dish or antenna transmits pulses of radio waves or microwaves which bounce off any object in their path. In 1922 A. Hoyt Taylor and Leo C. Young, researchers working with the U.S. Navy invented Radar.

Answer: (a)

Answer: (d)

A barometer is a scientific instrument used in meteorology to measure atmospheric pressure. Pressure tendency can forecast short term changes in the weather. Evangelista Torricelli is universally credited with inventing the barometer in 1643.

Answer: (d)

The aneroid barometer is an instrument for measuring pressure as a method that does not involve liquid. Invented in 1844 by French scientist Lucien Vidi, it uses a small, flexible metal box called an aneroid cell, which is made from an alloy of beryllium and copper.

Answer: (a)

The spectroheliograph is an instrument used in astronomy which captures a photographic image of the Sun at a single wavelength of light, a monochromatic image. The wavelength is usually chosen to coincide with an spectral wavelength of one of the chemical elements present in the Sun.

Answer: (c)

A eudiometer is a laboratory device that measures the change in volume of a gas mixture following a physical or chemical change. Applications of a eudiometer include the analysis of gases and the determination of volume differences in chemical reactions.

It is similar in structure to the meteorological barometer.