no, it not useless. we still learn Bohr's model in HS n dats almost 200 yr old! while there may be new models, previous one is good for explaining the basics. it is also useful to learn previous model n see how our understanding improves over time.
Answer:
13.6 cm
Explanation:
From Snell's law:
n₁ sin θ₁ = n₂ sin θ₂
In the air, n₁ = 1, and light from the horizon forms a 90° angle with the vertical, so sin θ₁ = sin 90° = 1.
Given n₂ = 4/3:
1 = 4/3 sin θ
sin θ = 3/4
If x is the radius of the circle, then sin θ is:
sin θ = x / √(x² + 12²)
sin θ = x / √(x² + 144)
Substituting:
3/4 = x / √(x² + 144)
9/16 = x² / (x² + 144)
9/16 x² + 81 = x²
81 = 7/16 x²
x ≈ 13.6
Im not 100% sure you have to tell me if im wrong or not.
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B
C
Answer:

Explanation:
<u>Displacement Vector</u>
Suppose an object is located at a position

and then moves at another position at

The displacement vector is directed from the first to the second position and can be found as

If the position is given as magnitude-angle data ( z , α), we can compute its rectangular components as


The question describes the situation where the initial point is the base of the mountain, where both components are zero

The final point is given as a 520 m distance and a 32-degree angle, so


The displacement is
