Recent content by ryank614

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    How did Apollo get to the moon?

    Q: What kind of trajectory was used? And why was it used over the Hohmann transfer? The time of flight to the moon on Apollo 11 was 100 hours, 39 minutes 53 seconds. The time of flight for a Hohmann transfer would have been 119 hours from my calculations. I've done some research and found...
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    Dynamics Question with Rotational Axis Theorem

    Homework Statement A cyclist rides around a circular track (R= 30m) such that the point of contact of the wheel on the track moves at a constant speed of 10m/s. The bicycle is banked at 15 degrees inward from the vertical. Find the acceleration of a tack in the tire (.4m radius) as it passed...
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    Differentiate the law of Cosine

    Arr, nevermind. I got it.
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    Differentiate the law of Cosine

    It is a simple math question, but I am stuck. The law of cosines is R^2=h^2 + r^2 - 2 h r cos (theta). Theta is of course the angle facing R. To differentiate, I first set r^2 - 2hr cos\Theta+ (h^2-R^2) = 0 2 r \dot{}r - 2 h cos\Theta \dot{}r + (h^2-R^2) = 0. Is there any...
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    Semimajor Axis and Eccentricity after increased velocity

    Question: A space shuttle is in an orbit about the Earth. At its apogee, it uses thrusters and increases its velocity by 400 m/sec. What is the new orbit semimajor axis, eccentricity and how much will the next perigee altitude be increased? Known: Original semimajor axis: 7000 km -> a...
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    Orbit Semimajor Axis and Eccentricity after increasing V

    Question: A space shuttle is in an orbit about the Earth. At its apogee, it uses thrusters and increases its velocity by 400 m/sec. What is the new orbit semimajor axis, eccentricity and how much will the next perigee altitude be increased? Known: Original semimajor axis: 7000 km -> a...
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    Figuring out time to center of the Earth via a vacuum hole

    Wow. Thank you very much. I just plugged in w and divided by 4 since it was asking for the time to the center. Thanks!
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    Figuring out time to center of the Earth via a vacuum hole

    Ok, so you are saying the double integral of s + gs/R(e) = 0. I can't completely see how that helps me the time. Unless, are you saying that g/R(e) is equal to w?
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    Figuring out time to center of the Earth via a vacuum hole

    Homework Statement A hole is drilled from the North to South pole. THe air is evacuated. An object dropped from the surface would accelerate at a=-gs/R(e), where s is the distance of the object from the center of the Earth. Find the magnitude of velocity at the middle of the Earth and the...
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