Questions

Concave type of glasses are used in the headlights of the vehicles as the light from the bulb which is at focus will converges out and spreads and reflects back parallely.

A device which is used to convert light energy directly into electrical energy is called as photovoltaic cell or a solar cell.

Heliostats convert light energy into heat energy.

A thermocouple is a device for measuring temperature.

Alfred Bernhard Nobel was a Swedish chemist, engineer, inventor, businessman, and philanthropist. Known for inventing Dynamite, Nobel also owned Bofors, which he had redirected from its previous role as primarily an iron and steel producer to a major manufacturer of cannon and other armaments.

A person who builds houses or buildings is known as builder.

In the form of vinegar, acetic acid is known from very early times. It is got by oxidation of fermented liquors (10-15%, alcohol) by air under the influence of a bacteria called 'mycoderma acetic'

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Argentine Star Lionel Messi was chosen as the World’s Best Playmaker for the year 2016 on December 29, 2016, by the International Federation of Football History and Statistics (IFFHS). Messi topped the list with 172 points followed by Andres Iniesta at second spot with 66 points and Toni Kross third with 45 points.