Recent content by rockchalk1312

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    Does this horsepower for this car seem like the right value?

    For a lab in physics where we have to go through an enormous process to calculate the drag coefficient, I am trying to figure out if one of the values I got along the way makes sense so that I don't continue with bad data. I gathered time and speed deceleration data and drove a 2002 Honda...
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    Using displacement, velocity and acceleration oscillation equation?

    Homework Statement The function x = (4.5 m) cos[(6∏ rad/s)t + ∏/3 rad] gives the simple harmonic motion of a body. At t = 1.6 s, what are the (a) displacement, (b) velocity, (c) acceleration, and (d) phase of the motion? Also, what are the (e) frequency (in Hz) and (f) period of the...
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    Finding period of revolution of stars?

    But I used their masses--7 x that of the earth--and their separation is 7x the distance between the sun and the Earth (1 amu).
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    Finding period of revolution of stars?

    Doesn't that mean you have to know the radius of the stars themselves?
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    Finding period of revolution of stars?

    ...I wish I knew what that implies...
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    Finding period of revolution of stars?

    Homework Statement In a certain binary-star system, each star has the same mass which is 7.5 times of that of the Sun, and they revolve about their center of mass. The distance between them is the 7.5 times the distance between Earth and the Sun. What is their period of revolution in years...
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    Calculating net force on four masses around a center mass?

    Well what I don't know how to do is break up a diagonally pointing force into i and j components. And by "has a factor mi", do you mean that the j component of each force is the same? If so why is that? Would you just add up the four vectors' i components and multiply that by the equation you...
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    Calculating net force on four masses around a center mass?

    In the figure, a square of edge length 16.0 cm is formed by four spheres of masses m1 = 4.50 g, m2 = 2.80 g, m3 = 0.800 g, and m4 = 4.50 g. In unit-vector notation, what is the net gravitational force from them on a central sphere with mass m5 = 2.10 g? F = G (m1m2/r2) To get the...
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    Calculating dA/dB ratio for horizontal log?

    What exactly do you mean by deflection? Is it just asking for the ratio of the change in length of A to B? B doesn't change in length so that would make the ratio invalid...
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    Calculating stress, strain and Young's modulus?

    All of those helped me! The computer just wanted them entered in an odd way. Thank you!
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    Calculating dA/dB ratio for horizontal log?

    In the figure, a 105 kg uniform log hangs by two steel wires, A and B, both of radius 1.25 mm. Initially, wire A was 2.50 m long and 1.80 mm shorter than wire B. The log is now horizontal. Young's modulus for steel is 2.00 × 1011 N/m2. What is the ratio dA/dB? I'm honestly at a loss for how...
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    Calculating stress, strain and Young's modulus?

    After a fall, a 77 kg rock climber finds himself dangling from the end of a rope that had been 15 m long and 9.1 mm in diameter but has stretched by 2.3 cm. For the rope, calculate (a) the strain, (b) the stress, and (c) the Young's modulus. strain = ΔL/L stress = F/A Young's modulus =...
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    Finding angular speed & KE using moment of inertia?

    In the figure, two skaters, each of mass 48.1 kg, approach each other along parallel paths separated by 2.90 m. They have opposite velocities of 1.61 m/s each. One skater carries one end of a long pole of negligible mass, and the other skater grabs the other end as she passes. The skaters then...
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