Answer:
v = 9.04 m / s
Explanation:
For this exercise we can use the relation that the work of the non-conservative force (friction) is equal to the variation of the mechanical energy of the system.
W = Em_f - Em₀ (1)
Starting point. Lower slope
Em₀ = K = ½ m v²
highest point. Where is the skier at a height h
Em_f = U = m g h
The work of rubbing
W = -fr x
the negative sign is because the friction force opposes the movement.
Let's set a reference system where the x axis is parallel to the slope and the y axis is perpendicular
let's use trigonometry to break down the weight
cos θ = W_y / W
sin θ = Wₓ / W
W_y = W cos θ
Wₓ = W sin θ
Y axis
N - Wₓ = 0
N = mg sin θ
X axis
fr = m a
the friction force has the expression
fr = μ N
fr = μ mg sin θ
we look for the job
W = - μ mg sin θ x
where x is the distance along the slope
we substitute in 1
-μ mg sin θ x = mg h - ½ m v²
let's use trigonometry to find the distance x
tan 30 = h / x
x = h / tan 30
we substitute
- 
= m gh - ½ m v²
we use
tan 30 = sin30 / cos30
v² = 2g h + 2 μ g h cos 30
v = 
let's calculate
v = 
v = 9.04 m / s
1449 is the answer to the question
The two kinds of motion are horizontal and vertical
Answer:
stomata to regulate water
specialized cells
Explanation:
Land plants are able to successfully adapt to staying on land through the use of stomata to regulate water loss and through the development of specialized cells that give support to grow erect.
Water regulation is important for the survival of plants on land, otherwise, they may face desiccation as a result of the heat from the sun. <u>The stomata is a structure found on the leaves of land plants that open and close to regulate the amount of water lost to the environment through evapotranspiration.</u> When there is adequate water and the plant can afford to lose some water, the stomata open, otherwise, the stomata close.
Support is also important for land plant's survival and the development of specialized cells in the form of <em>sclerenchyma cells</em> take care of this. The <em>fib</em>ers and <em>sclerids</em> are two types of sclerenchyma cells that primarily function to support the land plants.
Answer:
- Hydrogen and Helium
- Rock
- Metals
- Hydrogen compounds
Ranked from left to right based on their abundance in the solar nebula:
Hydrogen and Helium-Hydrogen compounds-Rocks-Metals
I hope you find this information useful and interesting! Good luck!
