Abundant energy: Fusing atoms together in a controlled way releases nearly four million times more energy than a chemical reaction such as the burning of coal, oil or gas and four times as much as nuclear fission reactions (at equal mass)
Answer:
a)
, b) ![\Delta K = 9.559\times 10^{-5}\,J](https://tex.z-dn.net/?f=%5CDelta%20K%20%3D%209.559%5Ctimes%2010%5E%7B-5%7D%5C%2CJ)
Explanation:
a) The final velocity of the 13.5 g coin is found by the Principle of Momentum Conservation:
![(4.5\times 10^{-3}\,kg)\cdot (23.8\times 10^{-2}\,\frac{m}{s} )+(13.5\times 10^{-3}\,kg})\cdot (0\,\frac{m}{s} ) = (4.5\times 10^{-3}\,kg)\cdot (-11.9\times 10^{-2}\,\frac{m}{s} )+(13.5\times 10^{-3}\,kg})\cdot v](https://tex.z-dn.net/?f=%284.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%29%5Ccdot%20%2823.8%5Ctimes%2010%5E%7B-2%7D%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%2B%2813.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%7D%29%5Ccdot%20%280%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%20%3D%20%284.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%29%5Ccdot%20%28-11.9%5Ctimes%2010%5E%7B-2%7D%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%2B%2813.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%7D%29%5Ccdot%20v)
The final velocity is:
![v = 11.9\times 10^{-2}\,\frac{m}{s} \,(11.9\,\frac{cm}{s} )](https://tex.z-dn.net/?f=v%20%3D%2011.9%5Ctimes%2010%5E%7B-2%7D%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%5C%2C%2811.9%5C%2C%5Cfrac%7Bcm%7D%7Bs%7D%20%29)
b) The change in the kinetic energy of the 13.5 g coin is:
![\Delta K = \frac{1}{2}\cdot (13.5\times 10^{-3}\,kg)\cdot \left[(11.9\times 10^{-2}\,\frac{m}{s} )^{2}-(0\,\frac{m}{s} )^{2}\right]](https://tex.z-dn.net/?f=%5CDelta%20K%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20%2813.5%5Ctimes%2010%5E%7B-3%7D%5C%2Ckg%29%5Ccdot%20%5Cleft%5B%2811.9%5Ctimes%2010%5E%7B-2%7D%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%5E%7B2%7D-%280%5C%2C%5Cfrac%7Bm%7D%7Bs%7D%20%29%5E%7B2%7D%5Cright%5D)
![\Delta K = 9.559\times 10^{-5}\,J](https://tex.z-dn.net/?f=%5CDelta%20K%20%3D%209.559%5Ctimes%2010%5E%7B-5%7D%5C%2CJ)
Answer:
W = 30 N
Explanation:
Applying the summation of torques about the wedge for equilibrium, taking the clockwise direction as negative. Since the ruler is balanced horizontally about the wedge. Therefore, the summation of all torques acting about the wedge must be equal to zero.
![(70\ N)(40\ cm - 10\ cm)-(30\ N)(50\ cm-40\ cm)-(W)(100\ cm - 40\ cm) = 0\\W(60\ cm) = (70\ N)(30\ cm)-(30\ N)(10\ cm)\\\\W = \frac{1800\ N.cm}{60\ cm}](https://tex.z-dn.net/?f=%2870%5C%20N%29%2840%5C%20cm%20-%2010%5C%20cm%29-%2830%5C%20N%29%2850%5C%20cm-40%5C%20cm%29-%28W%29%28100%5C%20cm%20-%2040%5C%20cm%29%20%3D%200%5C%5CW%2860%5C%20cm%29%20%3D%20%2870%5C%20N%29%2830%5C%20cm%29-%2830%5C%20N%29%2810%5C%20cm%29%5C%5C%5C%5CW%20%3D%20%5Cfrac%7B1800%5C%20N.cm%7D%7B60%5C%20cm%7D)
<u>W = 30 N</u>