Il A heavy ball with a weicht of 100 N (m 10.2 kg) is hung. from the ceiling of a lecture hall on a 4.5-m-long rope. The ball. is pulled to one side and released to swing as a pendulum, reach-. ing a speed of 5.5 m/s as it passes throuoh the lowest point.
Inventions. The huochong gun was invented in China during the Ming dynasty. It was also called the tongjiangjun, which meant bronze general. This was an important invention of the time period because the Ming Dynasty was creating weapons to defend their dynasty, and they came across the gun.t was also called the tongjiangjun, which meant bronze general. This was an important invention of the time period because the Ming Dynasty was creating weapons to defend their dynasty, and they came across the gun.
This was one of the greatest Ming Dynasty inventions and was introduced in 1403. This inspired todayâs encyclopedia. The Ming Dynasty is considered to be one of the most prosperous and glorious periods in the history of China.Apart from the enchanting attractions, spectacular artifacts, and the Great Wall, the Ming Dynasty was also known for its wonderful innovations.his invention occurred around 1498, during the reign of the Hongzhi Emperor of the Ming Dynasty. This was mass-produced in 1780, several years after the fall of the Ming Dynasty. Before the toothbrush was invented, people used sticks and flared edges called chew sticks. After this, pig bristles were used.