Question

Classification of Gears with Example...​

Answer 1

Answer:

Gears are classified into 3 categories; parallel axes gears, intersecting axes gears, and nonparallel and nonintersecting axes gears. Spur gears and helical gears are parallel axes gears. Bevel gears are intersecting axes gears. Screw or crossed helical, worm gear and hypoid gears belong to the third category

Answer 2

Explanation:

The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. The word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors.