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DerKrebs [107]
2 years ago
9

A student on the ground observes the sun just as it sets. His friend, who is located 100 meters higher up in a tall building, te

lls him via cell phone that she observes the sun setting 77 seconds after he does. Assuming that the path of the setting sun is perpendicular to the horizon, use this information to estimate the radius of the Earth.

Physics
1 answer:
FrozenT [24]2 years ago
4 0

Answer:

Rt≅6377Km

Explanation:

Take a look at the image. The horizontal line is the horizon, and the angle α corresponds to the earth rotation during the 77 seconds.

With this information, we can know the value of α:

α = \alpha= \frac{77s}{1day}*\frac{1day}{24H}*\frac{1H}{60min}*\frac{1min}{60s}*2*\pi  =0.0056rad

Since we have formed a rectangle triangle:

cos\alpha =\frac{Rt}{Rt+100m}   Solving for Rt:

Rt≅6377467m=6377Km

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Answer:

The discharge of the stream at this location is 40 cubic meters per second.

Explanation:

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A basketball is thrown upwards. The height f(t), in feet, of the basketball at time t, in seconds, is given by the following fun
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3 years ago
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A soccer ball kicked with a force of 12.5 N accelerates at 6.2 m/s’ to the right. What is the mass of the ball? Answer in units
stepladder [879]

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Explanation:

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How much energy is required to heat 70 g of water at 20°C to boiling
choli [55]

Answer:

Q=23,430J

Explanation:

Hello,

In this case, since we compute the required energy via:

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Best regards.

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3 years ago
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