4-C. ... 5-D. ... 6-A. ... 7-D. ... 8-C. ... 9-B. ... 10-D. It's really a joy and a delight that you've learned so much by posting all of these questions.
Answer:
Ek = 1705.28 [J]
Explanation:
In order to solve this problem, we must remember that kinetic energy can be calculated by means of the following equation.
where:
m = mass [kg]
v = velocity [m/s]
Ek = kinetic energy [J] (Units of Joules)
<u>For the person running</u>
<u />![E_{k} =\frac{1}{2}*52.2*(3.5)^{2} \\ E_{k} =319.72[J]](https://tex.z-dn.net/?f=E_%7Bk%7D%20%3D%5Cfrac%7B1%7D%7B2%7D%2A52.2%2A%283.5%29%5E%7B2%7D%20%5C%5C%20E_%7Bk%7D%20%3D319.72%5BJ%5D)
<u />
<u />
<u>For the bullet</u>
<u />
<u />
<u />![E_{k} =\frac{1}{2} *0.02*(450)^{2} \\E_{k}=2025 [J]](https://tex.z-dn.net/?f=E_%7Bk%7D%20%3D%5Cfrac%7B1%7D%7B2%7D%20%2A0.02%2A%28450%29%5E%7B2%7D%20%5C%5CE_%7Bk%7D%3D2025%20%5BJ%5D)
<u />
<u />
The difference in Kinetic energy is equal to:
Ek = 2025 - 319.72
Ek = 1705.28 [J]
12. The answer would be C. 1.50 s. This is because if you divide 60 by 40, you will get 1.5.
13. For this one I'm not sure, but what I can tell you is that the heavier something is the faster it will sink, the lighter it is, it will float.
Answer:
Explanation:
The relationship of the speed of sound, its frequency, and wavelength is the same as for all waves: vw = fλ, where vw is the speed of sound, f is its frequency, and λ is its wavelength.
