When a balloon is warmed by a lamp it just pops
Answer:
The early observations in Astronomy were used to determine the length of the year and to determine the seasons, which is an important factor in knowing when plants will grow. In the early days, astronomy consisted only of observations and projections of objects that could be seen by ordinary eyes.
Explanation:
Astronomy is the oldest of the modern natural sciences. It probably came with the need for a calendar. In ancient times, astronomers were monks, shamans, druids, and priests. At that time, astronomy was considered astrological. In some places, early civilizations have created great spaces for some astronomical purposes. In addition to rituals, these early observations were used to determine the length of the year and to determine the seasons, which is an important factor in knowing when plants will grow. In the early days, astronomy consisted only of observations and projections of objects that could be seen by ordinary eyes. According to some estimates, Stonheng, the Ziggurats in Mesopotamia, and the Pyramids of the Stones and the Chinese are the oldest observatory. Moon calendars are still considered very accurate today. Similarly, Chinese star catalogs are a valuable source for studying ancient astronomical events. Greek scholars made a special contribution to the development of astronomy. Aristotle, Ptolemy, Hipparchus, Fales, Aratos were engaged in astronomy along with other scientific discoveries. Ptolemy has developed the Geocentric Theory to explain the planetary movement of planets. According to this theory, the earth remains stationary in the center of the world, and all the celestial bodies revolve around it. Ptolemy commented regularly on Almagest. The training continued until the 16th century. Despite religious resistance, this training has been replaced by training in the world's heliocentric system. It is thought that the 6,500-year-old megaliths (Nabta Playa, Stonehenge), planted by ancient people, were used for astronomical observation. In the Rig Veda, there are 27 constellations and 13 separate constellations associated with the movement of the sun. The most important contribution made by ancient Greeks to astrology is that they have tried to classify stars according to their size.
We have discovered 786 planets. Most of which were only recently discovered.
Answer:
m = 170 g
Explanation:
Meter stick is suspended at 40 cm mark
So here the torque due to additional mass and torque due to weight of the spring must be counter balanced
given that
1) 220 g is suspended at x = 5 cm
2) 120 g is suspended at x = 90 cm
3) mass of the scale is acting at its mid point i.e. x = 50 cm
now with respect to the suspension point the torque must be balanced
so we have
by solving above equation we have
m = 170 g
