Recent content by whitetiger

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    Finding Total B-Field and Direction in a Wire-Magnet System

    Thank for the advice. From the RHR, the magnetic field is pointing in the x-axis direction, similar to B_o. The value for B_o is given as 1.50 x 10^-6 T, so the total B field will then be 1.50 x 10^-6 + 1.6 x 10^-6 T = 1.0 x 10^-7 T. I am still confuse on how to find the angle, can...
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    Finding Total B-Field and Direction in a Wire-Magnet System

    Homework Statement A long, straight wire lies along the y-axis and carries a current I = 8.00 A in the -y-direction . In addition to the magnetic field due to the current in the wire, a uniform magnetic field with magnitude is in the +x-direction. What is the magnitude of the total...
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    Extreme Period for a Physical Pendulum

    I think I've got it. P = 2pi(sqrt(a^2/2gd + d/g)) If you look at this, how can you determine whether it has a local maximum or local minimum for some value of d?
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    Extreme Period for a Physical Pendulum

    Thank for the useful info. Is this the correct moment of inertia of the disk about the pivot point. I= 1/2Ma^2 + Md^2 = M ( 1/2a^2 + d^2) So the period of the disk is P = 2pi (sqrt (M(1/2a^2 + d^2))
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    Extreme Period for a Physical Pendulum

    So is this right : I = 1/2Ma^2 P = P= 2pi (sqrt 1/2Ma^2/(1/2Mgd^2)) == then we can cancel out the M to get P = 2pi (sqrt 1/2a^2/(1/2gD^2)) === cancel 1/2 === P = sqrt(a^2/gd^2)
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    Extreme Period for a Physical Pendulum

    Homework Statement http://img120.imageshack.us/img120/808/periodicemotionhd3.jpg solid, uniform disk of mass M and radius a may be rotated about any axis parallel to the disk axis, at variable distances from the center of the disk If you use this disk as a pendulum bob, what is T(d), the...
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    What is the Period of Oscillation Based on Given Coordinates?

    Thank for the help From what you have said, I can calculate the total period to be (.005)4 = .02s
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    What is the Period of Oscillation Based on Given Coordinates?

    Homework Statement Now assume that the x coordinate of point R is 0.12m and the t coordinate of point K is 0.0050 s. What is the period T ? Homework Equations T = 1/f where f is the frequency and T is the period. The Attempt at a Solution From the graph, there are 2...
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    Speed of spacecraft (gravitational force)

    Thank you KoGs for replying to my question. I have finally figure our how to solve the problem. First I have to balance the centripetal force and the centrifugal forces. After finding the initial kinetic energy and the energy due to falling I was able to find the speed at which it hits the...
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    Speed of spacecraft (gravitational force)

    An unmanned spacecraft is in a circular orbit around the moon, observing the lunar surface from an altitude of 43.0 km (see Appendix F). To the dismay of scientists on earth, an electrical fault causes an on-board thruster to fire, decreasing the speed of the spacecraft by 20.0 m/s. If...
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    Find the satellite's altitude above the earth's surface

    I think we have to use the radius of the Earth to calculate for the satellite's altitude So the above equation F = mgU = mgh U=Fh h= U/F is not correct
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    Find the satellite's altitude above the earth's surface

    Yes, I have tried F=mg U=mgh U=Fh h=U/F and substituting in 1.49×10^11 J/ 15.1 kN. But I've got the wrong answer. Can someone comment more on this Thank
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    Find the satellite's altitude above the earth's surface

    When in orbit, a communication satellite attracts the Earth with a force of 15.1 kN and the earth-satellite gravitational potential energy (relative to zero at infinite separation) is - 1.49×10^11 J. Take the radius of the Earth to be r_e = 6.38×106 m. Find the satellite's altitude above the...
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    Gravitational Acceleration inside a Planet

    Thank you for the help. I have finally figured out the problem.
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    Gravitational Acceleration inside a Planet

    Consider a spherical planet of uniform density p. The distance from the planet's center to its surface (i.e., the planet's radius) is R_p. An object is located a distance R from the center of the planet, where R < R_p. (The object is located inside of the planet.) Find an expression for the...
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