Worksheet Solutions: Scientists and Inventors | General Knowledge Encyclopedia - Class 8 PDF Download

Multiple Choice Questions (MCQs)

Q1: Who is credited with the invention of the telephone?
(a) Thomas Edison
(b) Alexander Graham Bell
(c) Nikola Tesla
(d) Benjamin Franklin

Ans: (b)
Explanation: Alexander Graham Bell is credited with inventing the telephone in 1876. He was a Scottish-born scientist and inventor who immigrated to the United States. His invention revolutionized communication and laid the foundation for the modern telephone network.

Q2: Who discovered the theory of relativity?
(a) Isaac Newton
(b) Albert Einstein
(c) Marie Curie
(d) Galileo Galilei

Ans: (b)
Explanation: Albert Einstein, a German-born physicist, developed the theory of relativity. His famous equation, E=mc², demonstrates the relationship between energy and mass. This groundbreaking theory transformed our understanding of space, time, and gravity.

Q3: Who is known for discovering the law of gravity?
(a) Isaac Newton
(b) Albert Einstein
(c) Galileo Galilei
(d) Nikola Tesla

Ans: (a)
Explanation: Isaac Newton, an English mathematician, physicist, and astronomer, discovered the law of gravity in the late 17th century. His laws of motion and the law of universal gravitation laid the groundwork for classical physics.

Q4: Who invented the light bulb?
(a) Thomas Edison
(b) Alexander Graham Bell
(c) Nikola Tesla
(d) Wright brothers

Ans: (a)
Explanation: Thomas Edison, an American inventor, is credited with inventing the practical incandescent light bulb in 1879. He made significant contributions to various fields, including electric power generation, motion pictures, and sound recording.

Q5: Who discovered penicillin?
(a) Louis Pasteur
(b) Alexander Fleming
(c) Marie Curie
(d) Gregor Mendel

Ans: (b)
Explanation: Alexander Fleming, a Scottish biologist and pharmacologist, discovered penicillin in 1928. This chance discovery of the mold Penicillium notatum led to the development of the first widely used antibiotic, revolutionizing medicine.

Q6: Who invented the computer?
(a) Bill Gates
(b) Steve Jobs
(c) Charles Babbage
(d) Mark Zuckerberg

Ans: (c)
Explanation: Although modern computers evolved over time, Charles Babbage, an English mathematician and engineer, is often considered the "father of the computer." He conceptualized and designed the Analytical Engine, a mechanical precursor to the computer, in the 19th century.

Q7: Who discovered the polio vaccine?
(a) Jonas Salk
(b) Louis Pasteur
(c) Alexander Fleming
(d) Edward Jenner

Ans: (a)
Explanation: Jonas Salk, an American medical researcher, developed the first successful polio vaccine in the 1950s. His vaccine effectively eradicated the disease in many parts of the world and significantly reduced polio-related illnesses and deaths.

Q8: Who invented the printing press?
(a) Johannes Gutenberg
(b) Leonardo da Vinci
(c) James Watt
(d) Eli Whitney

Ans: (a)
Explanation: Johannes Gutenberg, a German blacksmith, goldsmith, and inventor, is credited with inventing the printing press in the 15th century. His invention revolutionized the mass production of books, leading to increased literacy and the spread of knowledge.

Q9: Who discovered the laws of heredity?
(a) Isaac Newton
(b) Albert Einstein
(c) Gregor Mendel
(d) Marie Curie

Ans: (c)
Explanation: Gregor Mendel, an Austrian monk and botanist, is known as the "father of modern genetics." In the mid-19th century, he conducted experiments on pea plants and discovered the basic laws of heredity, now known as Mendelian inheritance.

Q10: Who developed the theory of evolution by natural selection?
(a) Isaac Newton
(b) Charles Darwin
(c) Louis Pasteur
(d) Galileo Galilei

Ans: (b)
Explanation: Charles Darwin, an English naturalist and biologist, developed the theory of evolution by natural selection. His book "On the Origin of Species," published in 1859, revolutionized our understanding of how species evolve over time through the process of natural selection.