The speed of the boy and his friend at the bottom of the slope is 16.52 m/s.
<h3>Their speed at the bottom</h3>
Apply the principle of conservation of energy,
E(up) - E(friction) = E(bottom)
mg sin(15) + ¹/₂(M + m)u² - μ(M + m)cos 15 = ¹/₂(M + m)v²
![v = \sqrt{2[\frac{mgd \ sin15 \ + \frac{1}{2}(M + m)u^2 \ -\mu (M + m)g cos\ 15 }{M + m}] }](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%7B2%5B%5Cfrac%7Bmgd%20%5C%20sin15%20%5C%20%2B%20%5Cfrac%7B1%7D%7B2%7D%28M%20%2B%20m%29u%5E2%20%5C%20-%5Cmu%20%28M%20%2B%20m%29g%20cos%5C%2015%20%7D%7BM%20%2B%20m%7D%5D%20%7D)
where;
- u is the speed of the after 28 m
u = √2gh
u = √(2gL sin15)
u = √(2 x 9.8 x 28 x sin 15)
u = 11.92 m/s
![v = \sqrt{2[\frac{(30)(9.8)(70) \ sin15 \ + \frac{1}{2}(30 + 50)(11.92)^2 \ - 0.12 (30 + 50)9.8 cos\ 15 }{30 + 50}] }\\\\v = 16.52 \ m/s](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%7B2%5B%5Cfrac%7B%2830%29%289.8%29%2870%29%20%5C%20sin15%20%5C%20%2B%20%5Cfrac%7B1%7D%7B2%7D%2830%20%2B%2050%29%2811.92%29%5E2%20%5C%20-%200.12%20%2830%20%2B%2050%299.8%20cos%5C%2015%20%7D%7B30%20%2B%2050%7D%5D%20%7D%5C%5C%5C%5Cv%20%3D%2016.52%20%5C%20m%2Fs)
Thus, the speed of the boy and his friend at the bottom of the slope is 16.52 m/s.
Learn more about speed here: brainly.com/question/6504879
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This question is incomplete because the options are not given; here is the complete question:
Cardiorespiratory fitness improves the efficiency of the cardiovascular and the respiratory systems in delivering oxygen to the body.
Please select the best answer from the choices provided.
True
False
The correct answer to this question is True
Explanation:
The cardiorespiratory system (cardiovascular and respiratory system) includes structures and organs such as the heart, the lungs, the veins, etc. that are involved in the process of oxygenation of the body. This process can be less or more efficient depending on different factors. One of these is the cardiorespiratory fitness or the ability of the body to work effectively in terms of oxygenation during exercise or effort.
In this context, a higher cardiorespiratory fitness means the cardiorespiratory system will work more efficiently, while low fitness implies less efficient oxygenation. Additionally, this fitness can be improved through activities such as running, hiking, among others. Therefore, cardiorespiratory fitness improves efficiency in the process of oxygenation, which makes the statement true.
I would said A is the best option if i’m wrong sorry
Answer:
I think it's a true but I'm not the smartest
Answer:
They land at the same time.
Explanation:
Two masses falling through a vacuum (no air resistance or buoyancy forces) will accelerate at the same rate when dropped from the same height. Therefore, despite having different masses, they land at the same time.
