Answer:
Initial height L = 323.3m
Explanation:
Given:
Change in Length ∆L = 19.4cm 0.194m
Change in temperature ∆T = 41 -(-9) = 50°C
Coefficient of linear Thermal expansion of steel k = 12 × 10^-6 m/mK
Using the formula for linear expansion:
∆L = Lk∆T
L = ∆L/k∆T ....1
Substituting the given values into equation 1
L = 0.194/(12 × 10^-6 × 50)
Initial height L = 323.3m
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 Despite religious resistance, this training has been replaced by training in the world's heliocentric system.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.
Answer:
Force = mass × acceleration
Explanation:
The amount of force required to drag the object across the table is the product of the mass of the object and acceleration
<u>Answer:</u> The specific heat of ice is 2.11 J/g°C
<u>Explanation:</u>
When ice is mixed with water, the amount of heat released by water will be equal to the amount of heat absorbed by ice.
The equation used to calculate heat released or absorbed follows:
![m_1\times c_1\times (T_{final}-T_1)=-[m_2\times c_2\times (T_{final}-T_2)]](https://tex.z-dn.net/?f=m_1%5Ctimes%20c_1%5Ctimes%20%28T_%7Bfinal%7D-T_1%29%3D-%5Bm_2%5Ctimes%20c_2%5Ctimes%20%28T_%7Bfinal%7D-T_2%29%5D)
......(1)
where,
q = heat absorbed or released
= mass of ice = 12.5 g
= mass of water = 85.0 g
= final temperature = 22.24°C
= initial temperature of ice = -15.00°C
= initial temperature of water = 25.00°C
= specific heat of ice = ?
= specific heat of water = 4.186 J/g°C
Putting values in equation 1, we get:
![12.5\times c_1\times (22.24-(-15))=-[85.0\times 4.186\times (22.24-25)]](https://tex.z-dn.net/?f=12.5%5Ctimes%20c_1%5Ctimes%20%2822.24-%28-15%29%29%3D-%5B85.0%5Ctimes%204.186%5Ctimes%20%2822.24-25%29%5D)
Hence, the specific heat of ice is 2.11 J/g°C
Explanation:
Given:
v₀ = 0 m/s
v = 49 m/s
a = 9.8 m/s²
Find: t
v = at + v₀
49 m/s = (9.8 m/s²) t + 0 m/s
t = 5 s
