Recent content by balletgirl

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    Basic Geology: Magnetic Stripes and their relationship from ridge crests.

    Okay great! So the negative (lighter) stripes are reversed polarity... and the positive (darker) stripes are normal polarity?
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    Basic Geology: Magnetic Stripes and their relationship from ridge crests.

    Does the width of the stripes have to do with the time period between flipping polarity?
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    Basic Geology: Magnetic Stripes and their relationship from ridge crests.

    Homework Statement (Picture attached) How does the process of sea-floor spreading produce these orientations and relationships [between the ages of magnetic stripes and the distance from the ridge crests, as well as the parallel direction of the magnetic stripes with those of the ridge...
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    Magnitude and direction of the net force on charge -3Q and charge 4Q

    Homework Statement Four charges are located at the corners of a square as shown below. Calculate the magnitude and direction of the net force on charge -3Q and charge 4Q. (sorry don't have picture, but it is of a square with corners -Q, 2Q, -3Q, and 4Q clockwise). Homework...
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    Linear speeds at points on Earth

    Hello, The radius is 6.38 x 10^6 m. Would I add [Cos(θ)] to the equation v=rω and make it v=R*Cos(θ)*ω for parts b and c? (I tried it already for part b, but got a negative answer). By the way, I have v=463.83 m/s for part a.
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    Linear speeds at points on Earth

    I don't understand how to make this change though. Is there an equation I can use?
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    How Do You Calculate Angular Acceleration of a Wheel?

    Homework Statement A 70cm diameter wheels accelerates uniformly from 160 rpm to 280 rpm in 4.00s. Determine: a) it's angular acceleration, and b) the radial and tangential components of the linear acceleration of a point on the edge of the wheel 2.00s after it has started accelerating...
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    Linear speeds at points on Earth

    Homework Statement What is the linear speed of a point: a) on the equator, b) on the Arctic Circle (latitude 66.5 degrees N), c) at a latitude of 45 degrees N, due to the Earth's rotation? Given Radius (earth)= 6.38x10^6m v? Homework Equations v=rw w= 2pi*f t= 1/f The...
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    Concept Question. Record turntable rotates at constant angular velocity.

    Homework Statement Suppose a record turntable rotates at constant angular velocity. a) Does a point on the rim have radial and/or tangential acceleration? b) If the turntable's angular velocity increases uniformly, does the point have radial and/or tangential acceleration? c) For which...
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    Maximum speed Tarzan can tolerate

    Nevermind, I redid the problem and it makes much more sense now. I used f=ma, then a= F/m and got a= 17.5m/s^2. Then I used a=v^2/r and got v= 9.17m/s.
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    Maximum speed Tarzan can tolerate

    Homework Statement Tarzan plans to cross a gorge by swinging in an arc from a hanging vine. If his arms are capable of exerting a force of 1.4x10^3 N on the vine, what is the maximum speed he can tolerate at the lowest point of his swing? His mass is 80kg and the vine is 4.8m long...
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    What is the period of revolution for an artificial planet

    Homework Statement A science fiction tale describes an artificail "planet" in the form of a band completely encircling a sun, the inhabitants living on the inside surface (where it is always noon). Imagine the sun is like our own, that the distance to the band is the same as the Earth-Sun...
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    How many stars in our galaxy if they had the mass of our Sun.

    Okay, so I did T= 200,000,000 yrs = 6.31x10^15 s & R= 2.85x10^20 a=4pi^2*r/T^2 a= 4(3.14)^2*(2.85x10^20)/(6.31x10^15s) a=39.4(2.85x10^20)/3.98x10^31 a= 2.81x10^-10 I doubt this is right since it is negative
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    How many stars in our galaxy if they had the mass of our Sun.

    Homework Statement The Sun rotates about the center of the Milky Way Galaxy at a distance of about 3.00x10^4 light years from the center (1ly= 9.50x10^5 m). If it takes about 200 million years to make one rotation, estimate the mass of our galaxy. Assume the mass distribution of our galaxy...
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