<span>K.E = 0.5 * m * v^2 ( m = mass(Kg), V = Velocity(m/s)
= 0.5 * 8 * 5^2
= 4 * 25
= 100 J </span>
Answer:
43.7 °C
Explanation:
= Coefficient of linear expansion of brass = ![18\times 10^{-6}\ ^{\circ}C](https://tex.z-dn.net/?f=18%5Ctimes%2010%5E%7B-6%7D%5C%20%5E%7B%5Ccirc%7DC)
= Coefficient of linear expansion of steel = ![11\times 10^{-6}\ ^{\circ}C](https://tex.z-dn.net/?f=11%5Ctimes%2010%5E%7B-6%7D%5C%20%5E%7B%5Ccirc%7DC)
= Initial length of brass = 31 cm
= Initial length of steel = 11 m
= Total change in length = 3 mm
Total change in length would be
![\Delta L=\Delta L_b+\Delta L_s\\\Rightarrow \Delta L=L_{0b}\alpha_b\Delta T+L_{0s}\alpha_b\Delta T\\\Rightarrow \Delta T=\frac{\Delta L}{L_{0b}\alpha_b+L_{0s}\alpha_b}\\\Rightarrow \Delta T=\frac{0.003}{0.31\times 18\times 10^{-6}+11\times 10^{-6}\times 11}\\\Rightarrow \Delta T=23.7\ ^{\circ}C](https://tex.z-dn.net/?f=%5CDelta%20L%3D%5CDelta%20L_b%2B%5CDelta%20L_s%5C%5C%5CRightarrow%20%5CDelta%20L%3DL_%7B0b%7D%5Calpha_b%5CDelta%20T%2BL_%7B0s%7D%5Calpha_b%5CDelta%20T%5C%5C%5CRightarrow%20%5CDelta%20T%3D%5Cfrac%7B%5CDelta%20L%7D%7BL_%7B0b%7D%5Calpha_b%2BL_%7B0s%7D%5Calpha_b%7D%5C%5C%5CRightarrow%20%5CDelta%20T%3D%5Cfrac%7B0.003%7D%7B0.31%5Ctimes%2018%5Ctimes%2010%5E%7B-6%7D%2B11%5Ctimes%2010%5E%7B-6%7D%5Ctimes%2011%7D%5C%5C%5CRightarrow%20%5CDelta%20T%3D23.7%5C%20%5E%7B%5Ccirc%7DC)
![\Delta T=23.7\\\Rightarrow T_f-T_i=23.7\\\Rightarrow T_f=23.7+T_i\\\Rightarrow T_f=23.7+20\\\Rightarrow T_f=43.7\ ^{\circ}C](https://tex.z-dn.net/?f=%5CDelta%20T%3D23.7%5C%5C%5CRightarrow%20T_f-T_i%3D23.7%5C%5C%5CRightarrow%20T_f%3D23.7%2BT_i%5C%5C%5CRightarrow%20T_f%3D23.7%2B20%5C%5C%5CRightarrow%20T_f%3D43.7%5C%20%5E%7B%5Ccirc%7DC)
The final temperature is 43.7 °C
The answer they are looking for is the last one. However the last two are technically correct but the third one would result in negative work.
Answer:
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The greatest evidence for Sea-floor spreading is the oceanic trenches, the oceanic ridges, the magma protruding to the surface and the new seafloor.
In previous theories, continents were assumed to be transported across the sea. Harry Hess, in the 1960s, proposed the idea that the seabed itself moves as it expands from a central point. The theory is now accepted, and the phenomenon is thought to be caused by convection currents in the upper layer of the mantle.
In our community, every person takes a certain role in a way that they contribute something for the development of the community. Certain interactive roles include trainings, team buildings, meetings, fund raising, and etc. Every individual has also gained their own statuses depending on what they have achieved and what they have contributed as well. Those individuals that are classified in the higher statuses are those who are experienced and trained to lead. These roles and statuses help our community become better as well as helping the youth to be great models and individuals in the future.