Class 5 SST Question Answers - The Machine Age

Q1: What is a machine, and how can you describe it in simple terms?
Ans: A machine is something that helps make our work easier by doing tasks for us. It can replace or simplify the efforts of humans or animals in doing physical tasks.

Q2: Name some simple machines that have been used throughout history.
Ans: Some simple machines are the lever, wedge, wheel, pulley, and screw.

Q3: Why did early humans invent machines?
Ans: Early humans invented machines because they needed help to overcome obstacles and make their tasks easier. Sometimes, they didn't have enough energy to do the work themselves.

Q4: How did people use wood and stone in early times to make machines?
Ans: Early people used wood and stone to create tools like hammers, axes, spears, and even wheels. These tools were considered machines because they made tasks easier.

Q5: What happened when people discovered copper?
Ans: When people discovered copper, they used it to make various things, like utensils, and the heads of arrows and spears. Utensils are not machines, but the heads of arrows, spears, and axes are considered machines.

Q6: How did the discovery of iron impact the use of copper?
Ans: Iron replaced copper in many cases because it was stronger and more durable. People started using iron for various purposes.

Q7: What were the main sources of energy before the use of steam power?
Ans: Before the use of steam power, the main sources of energy were human power, animal power, and wind power (used in sailing boats).

Q8: Who is James Watt, and what significant invention is he known for?
Ans: James Watt is known for using steam power to run water pumps in 1769. This invention led to the development of various machines, including railway engines and ships, powered by steam.

Q9: What was the shift in the source of energy during the 18th to 20th centuries?
Ans: During the 18th to 20th centuries, there was a shift in the source of energy from human and animal power to steam power, which was generated by burning wood or coal.

Q10: What are some of the problems associated with the use of coal and petroleum as energy sources?
Ans: Both coal and petroleum produce greenhouse gases like carbon dioxide and carbon monoxide when burned. These gases are harmful to the environment and can pose life-threatening problems. Additionally, both coal and petroleum are exhaustible resources, meaning they will eventually run out.