Changes in Means of Transport

Logs of wood

Step 1: Think about the very early days when people lived near rivers. Step 2: Motor boats and ships have engines — these were invented much later. Step 3: Submarines are a very modern invention used mainly by soldiers. Step 4: In the early times, people used simple logs of wood to float across rivers. Step 5: Gradually, they learned to make rafts, then boats, and finally big ships — showing how water transport developed slowly over time.

The Wright Brothers

Step 1: The question is about the invention of the first aircraft. Step 2: Thomas Edison is famous for inventing the light bulb, not the aeroplane. Step 3: Albert Einstein was a famous scientist known for his theories, not for inventing the aeroplane. Step 4: Graham Bell invented the telephone. Step 5: The Wright Brothers invented the first aircraft in the early 20th century. Their invention gradually led to the modern aeroplanes we use today to travel to faraway places quickly.

Helicopter

Step 1: The question asks about the air vehicle used during natural calamities like floods and earthquakes. Step 2: Hot air balloons are mostly used for fun and cannot carry heavy loads quickly. Step 3: Drones are operated without a human pilot and are not used for rescue missions typically. Step 4: Rockets are used by astronauts to travel to space, not for rescue during floods. Step 5: Helicopters can reach difficult places like hills, mountains, and flood-affected areas where other vehicles cannot reach, making them perfect for rescue and relief operations.

Air pollution

Step 1: Think about what happens when a vehicle burns petrol or diesel. Step 2: It releases smoke and harmful gases into the air around us. Step 3: Noise pollution is caused by loud sounds, not smoke. Step 4: Water pollution means making water bodies dirty, which is not related to vehicle smoke. Step 5: When vehicles release smoke and make the air dirty and unhealthy to breathe, it is called air pollution. This can cause diseases like asthma and other breathing problems.