The first effective vaccine against polio was prepared by ?

Correct Answer: Leonardo DaVinci

Correct Answer: Submarine

Correct Answer:

Correct Answer: Charles Macintosh

Explanation:

Charles Macintosh (29 December 1766 ? 25 July 1843) was a Scottish chemist and inventor of waterproof fabrics.He devoted all his spare time to science, particularly chemistry, and before he was twenty resigned his clerkship to take up the manufacture of chemicals. In this he was highly successful, inventing various new processes. His experiments with one of the by-products of tar, naphtha, led to his invention of waterproof fabrics.

Correct Answer: CBSE

Correct Answer: Robert Brown

Explanation:

Robert Brown, Scottish botanist, Discovered The Nucleus of a Cell in 1831, London. When Brown was studying orchids under microscope when he observed an opaque area, which he called the "Areola" or "Nucleus", in the cells of the flower's outer layer.

The nucleus was also described by Franz Bauer in 1804 but in detail Robert Brown made it in 1831.

Correct Answer: Michael Faraday

Explanation:

Michael Faraday invented Electric Generator in 1831.

 

• The operating principle of electromagnetic generators was discovered in the years of 1831?1832 by Michael Faraday.

 

• The principle later called Faraday's law, is that an electromotive force is generated in an electrical conductor which encircles a varying magnetic flux.

 

Correct Answer: 1874

Explanation:

Joseph F. Glidden - Father of Barbed Wire.

• Glidden was born in New York in 1812. He invented Barbed Wire in 1873 and was granted the patent on Nov. 24, 1874. After a three year battle over the patent, which he eventually won received a patent for the modern invention in 1874 after he made his own modifications to previous versions.

Correct Answer: Chloroform

Correct Answer: Sir William Grove