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From a satellite 400 mi above the Earth, it is observed that the angle formed by the vertical and the line of sight to the horizon is theta = 65.266°. Use this information to find the radius of the Earth. (Round your answer to the nearest mile.)

a) 1,300 mi
b) 3,000 mi
c) 4,000 mi
d) 5,200 mi

User Xtlc
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Final answer:

To find the radius of the Earth, we can use trigonometry and the information given. From a satellite 400 mi above the Earth, the angle formed by the vertical and the line of sight to the horizon is theta = 65.266°. By using the tangent function and rearranging the equation, we can calculate the radius of the Earth to be approximately 348 miles.

Step-by-step explanation:

To find the radius of the Earth, we can use trigonometry and the information given. From a satellite 400 mi above the Earth, the angle formed by the vertical and the line of sight to the horizon is theta = 65.266°. We can use the tangent function to relate this angle to the height of the satellite and the radius of the Earth.

First, convert the height of the satellite to kilometers: 400 mi × 1.609 km/mi = 643.6 km.

Next, we can use the tangent function: tan(theta) = R / (R + h), where R is the radius of the Earth and h is the height of the satellite. Rearrange the equation to solve for R: R = h / (tan(theta) - 1). Plugging in the values, we get R ≈ 643.6 km / (tan(65.266°) - 1). Using a calculator, we find that tan(65.266°) ≈ 2.146, so R ≈ 643.6 km / (2.146 - 1) ≈ 643.6 km / 1.146 ≈ 561 km.

Converting the result back to miles, we get approximately 561 km × 0.621 mi/km ≈ 348 miles. Since we are rounding to the nearest mile, the radius of the Earth is approximately 348 miles.

User Adchilds
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