Recent content by ObviousManiac

  1. O

    Tangential Force Required to Slow Cylinder to a rest?

    OH I didn't even think about that... wow I'm really dropping the ball tonight. So: I = .5mr^2 F = Ia/r f = .5mr^2a/r = .5mra = (6000)(.9)(-81.125)/2 = -219037.5 N
  2. O

    Tangential Force Required to Slow Cylinder to a rest?

    isn't I = mr2 ? So would it be F = Iα/r F = mr2α/r = mrα ?
  3. O

    Tangential Force Required to Slow Cylinder to a rest?

    T = mr2a = 6000(.92)(-81.125) = -394267.5 rF = -394267.5 .9F = -394267.5 F = -394267.5/.9 F = - 438075 N ... Is this correct?
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    Tangential Force Required to Slow Cylinder to a rest?

    to find α, could I not do this?: wf = wi + αt wf = 0, so -wi = αt (where wi = 62 rpm/60 sec * 2π rad = 6.49 rad/s) so - 6.49 = α(.08) α = -81.125 rad/s2
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    Tangential Force Required to Slow Cylinder to a rest?

    Silly question - what is my θ?
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    Tangential Force Required to Slow Cylinder to a rest?

    Homework Statement a)-The massive grinder for wood-pulp in a newsprint paper factory, which can render about a half Tonne of wood into a thin soup in less than a minute, is essentially a stone cylinder of radius 0.900 m and mass about 6.00 Tonnes. An enormous motor spins this cylinder on its...
  7. O

    Calculating Total Force on Earth from Venus, Jupiter, and Saturn

    btw for anyone wondering the correct answer is 9.03×10^17 N
  8. O

    Calculating Total Force on Earth from Venus, Jupiter, and Saturn

    haha answered my own question there - I set the (3010.3) to be negative and that gave me the right answer. Thanks for the help!
  9. O

    Calculating Total Force on Earth from Venus, Jupiter, and Saturn

    Okay, so: Distance from Earth to corresponding planet: Venus = 1.500×108 km - 1.080×108 km = 42,000,000 km = 4.2E10 m Jupiter = 7.780×108 km - 1.500×108 km = 628,000,000 km = 6.28E11 m Saturn = 1.430×109 km - 1.500×108 km = 1,280,000,000 km = 1.28E12 m F = GME[(.888ME/(4.2E102) +...
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    Calculating Total Force on Earth from Venus, Jupiter, and Saturn

    Homework Statement Calculate the total force on the Earth due to Venus, Jupiter and Saturn, assuming all four planets are in a line (see figure). An amateur astronomer measures the masses to be MV = 0.888 ME, MJ = 324 ME, MS = 98.0 ME, and their distances from the Sun are 1.080×10^8 km...
  11. O

    How long will it take Micrometeorites to cover the moon ?

    I keep trying but it's not working out. Could you give me a little more?
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    How long will it take Micrometeorites to cover the moon ?

    True about the years - I really messed that up. How am I supposed to calculate the spherical shell?
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    How long will it take Micrometeorites to cover the moon ?

    Homework Statement If one micrometeorite (a sphere with a diameter of 1.50×10-6 m) strikes each square meter of the surface of the Moon each second (1 micrometeorite/m2/s), how many years will it take to cover the Moon to a depth of 1.80 m? Assume that after impact, the micrometeorites...
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    How Does Changing the Angle of a Third Polarizer Affect Light Intensity?

    Homework Statement A helium-neon laser emits a beam of unpolarized light thatpasses through three Polaroid filters, as shown in the figure . The intensity of the laser beam is I_{o}. Suppose the third filter were at an angle of 50˚, what would be the intensity at point C?Homework Equations I...
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    How Do You Calculate the Index of Refraction in a Prism?

    Sin(45-a) = nsin(a)cos(a) - cos(45)sin(a) ...doesn't this just introduce a new variable? (n?)