Concept explainers
(a)
The distance between the cow A and cow B.
(a)
Answer to Problem 70P
The distance between the cow A and cow B is
Explanation of Solution
The figure 1 shows the geometry of the problem says to use the law of cosines to known sides and angles of a triangle to the unknown sides and angle.
Here,
The laws of cosines are,
The cows in the meadow region, the triangle has sides
Here, the object A is cow A, object B is cow B, and object C is person.
From the law of cosine, find the side
Conclusion:
Substitute
Therefore, the distance between the cow A and cow B is
(b)
The angle between the person and cow B.
(b)
Answer to Problem 70P
The angle between the person and cow B is
Explanation of Solution
From part (a) use the law of cosine and find the angle
Rewrite the above equation for
Conclusion:
Substitute
Therefore, the angle between the person and cow B is
(c)
The angle between the person and cow A.
(c)
Answer to Problem 70P
The angle between the person and cow A is
Explanation of Solution
From part (a) use the law of cosine and find the angle
Rewrite the above equation for
Conclusion:
Substitute
Therefore, the angle between the person and cow A is
(d)
The angle between star B and Sun.
(d)
Answer to Problem 70P
The angle between star B and Sun is
Explanation of Solution
Here, the situation is, object A is considered as star A, object B is star B, and object C is our Sun, so the triangle has sides
Conclusion:
Refer part (b),
Substitute
Therefore, the angle between star B and Sun is
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Chapter 1 Solutions
Principles of Physics: A Calculus-Based Text
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