The weight of a person on or above the surface of the earth varies inversely as the square of the distance the person is from the center of the earth. A particular person weighs 179 pounds on the surface of the earth and the radius of the earth is 3900 miles. Determine the equation that relates weight, W, to the distance from the center of the earth, d, for this person.
a.
W = StartFraction 2,722,590,000 Over d EndFraction
b.
W = StartFraction 698,100 Over d EndFraction
c.
W = StartFraction 2,722,590,000 Over d squared EndFraction
d.
W = StartFraction 698,100 Over d squared EndFraction

Respuesta :

Answer:

[tex]\displaystyle W = \frac{2\,722\,590\, 000}{d^{2}}[/tex]
(Where [tex]W[/tex] refers to the apparent weight in pounds when measured on the surface of the Earth, and [tex]d[/tex] is measured in miles.)

Step-by-step explanation:

Given that [tex]W[/tex] is inversely proportional to the square of [tex]d[/tex], there exists a constant [tex]k[/tex] such that:

[tex]\displaystyle W = \frac{k}{d^{2}}[/tex].

The goal is to find the value of [tex]k[/tex]. Given that [tex]W = 179[/tex] when [tex]d = 3900[/tex]:

[tex]\displaystyle (179) = \frac{k}{(3900)^{2}}[/tex].

Rearrange to obtain:

[tex]\begin{aligned} k &= (179)\, (3900)^{2} \\ &= 2\, 722\, 590\, 000 \end{aligned}[/tex].

Hence, the relation between [tex]W[/tex] and [tex]d[/tex] would be:

[tex]\displaystyle W = \frac{2\,722\,590\, 000}{d^{2}}[/tex].