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.
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A tailwind means you add thed velocity of the tailwind to the velovity of the plane (no need for any vectors etc. so you just need (7.5x 102 ) +30 then convert it so it like one of the answers (btw - none of the answers is exactly correct - you need to round to get it) thats what you need to do to get the question
If you mean work out as in using calculations, I don't know how to help you. But there is a way to find out, using Fleming's left hand rule. I can't define it properly, and I don't want to copy-paste from another site, so I strongly recommend that you look it up. Try google, or more specific, BBC GCSE bitesize.
Hope this helps!
Answer:
The options are:
Test 1: Mix a teaspoon of sodium bicarbonate into a cup of warm water to see if it dissolves.
Test 2: Mix a teaspoon of sodium bicarbonate into a cup of vinegar to see if it fizzes.
Test 3: Heat a teaspoon of sodium bicarbonate in the oven to see if its melting point is less than 400 degrees Fahrenheit.
Which statement provides the best assessment of his tests?
The answer is Test 2: Mix a teaspoon of sodium bicarbonate into a cup of vinegar to see if it fizzes.
This is because it will indicate the chemical property of the sodium bicarbonate as a result of its reaction with another chemical compound, a vinegar.
Tests 1 and 3 will show a physical property of the substance as a result of the physical characteristics such as solubility and melting point .
According to meteoric material, the solar system was formed around <u>4.6 billion years</u> ago.
<h3>What substance makes up a meteorite?</h3>
- With just trace levels of sulphide and carbide minerals, they are primarily composed of iron-nickel metal.
- Many asteroids melted during the radioactive element decay in the early solar system, and the iron they carried, being dense, sank to the centre to create a metallic core.
<h3>What is the term for meteorite metal?</h3>
- Meteoric iron, also known as meteoritic iron, is a native metal and a protoplanetary-disk remnant from the early universe that is found in meteorites.
- It is mostly composed of the metals iron and nickel, primarily in the crystalline phases kamacite and taenite.
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