Recent content by ally1h

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    Calculating Quadriceps Force | Basic Torque Question Solution

    Listen, thank you for your time and effort, but your hints aren't helping me. I'm getting beyond frustrated because of my inability to do such a simple problem. I can't figure this out. I need someone to show me HOW to do this problem, not just give me hints and confuse me further, because that...
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    Calculating Quadriceps Force | Basic Torque Question Solution

    Tg = [cos(15)] x 5# x 8" = 38.64"# Tw = [cos(15)] x 10# x 15" = 144.89"#Qx = cos(15) x 1.5 = 1.45 Qy = sin(15) x 1.5 = 3.89 I must still be getting something wrong. From point A, the angle <QAX is 15 degrees and the angle <QAY is 90 degrees.
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    Calculating Quadriceps Force | Basic Torque Question Solution

    I'm sorry... I don't know. I was never good at Trig or Geometry and I haven't had to do any for the last 8 years. Is 30 too obvious an answer? I really have no clue...
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    Calculating Quadriceps Force | Basic Torque Question Solution

    So for the horizontal component: [sin(15)] x [1.5"] = 0.39 And the vertical component: [cos(15)] x [1.5"] = 1.45 For the sum of torques: (40"#) + (150"#) + (0.39) = 190.39"# 190.39"# - 1.45 = 188.94"# So for equilibrium, Q has to be 188.94? Yes? No?
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    Calculating Quadriceps Force | Basic Torque Question Solution

    Homework Statement Find the Quadriceps force (Q) necessary to maintain equilibrium in this system. G= 5#; G distance= 8" W= 10#; W distance= 15" Q=? ; Q distance= 1.5" Theta 1 = 30 degrees Theta 2 = 15 degrees Here is a picture of the diagram...
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    How Is the Atomic Radius of Barium Calculated in a BCC Lattice?

    Ah... never mind. I was using the wrong equation. :) A = 4r/√3 4r = (502 pm)(√3) 4r = 869.5 pm r = 217 pmThanks anyway!
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    How Is the Atomic Radius of Barium Calculated in a BCC Lattice?

    Homework Statement Barium metal crystallizes in a body centered cubic lattice. The unit cell edge length is 502pm. Calculate the atomic radius of Ba. a) 251 pm b) 217 pm c) 177 pm d) 125 pm e) 63 pm Homework Equations Pythagorean Theorem The Attempt at a Solution A^2 + B^2...
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    The reducing agent in this redox equation?

    Homework Statement Which is the reducing agent in this equation, if any? Cr2O7 2- + 2OH- --> 2CrO4 2- +H2O Homework Equations The Attempt at a Solution After giving the elements their oxidation numbers I found the reducing agent to be Cr2O7 2- Is this correct?
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    Percentage of upolarized light

    Homework Statement Unpolarized light is passed through a polarizer-analyzer combination. The transmission of the polarizer and the analyzer are at 30 degrees to each other. What percentage of the unpolarized light gets through the combination? Homework Equations The Attempt at a...
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    Find the image distance - optical instruments

    Well now... don't I feel silly? Thank you.
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    Find the image distance - optical instruments

    Homework Statement An object is placed at 30 cm in front of a diverging lens with a focal length of 10 cm. What is the image distance? Homework Equations 1/f = 1/do + 1/di The Attempt at a Solution I thought this was a straight-forward question: 1/di = 1/-f - 1/do 1/di =...
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    Joules required to accelerate 1kg of mass

    Homework Statement how many joules of energy are required to accelerate 1 kg of mass from rest to a velocity of 0.866c? I tried the relativistic kinetic energy equation, but I feel like it's totally incorrect. Homework Equations KE = [(m0c^2) / √(1-v^2/c^2)] - m0c^2 E = KE + m0c^2...
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    Length Contraction: What Does it Mean for Mass?

    Homework Statement A spear moves past you at a very high speed. As it passes, you measure its length at one half its normal length. From this measurement, what can you conclude about the moving spear's mass? Homework Equations The Attempt at a Solution To have the spear appear...
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    Mass of a particle at speed of light

    Homework Statement I remember hearing in class that the mass of a particle nears infinity as the speed of the particle nears the speed of light. Is this true? And why is this true? Homework Equations The Attempt at a Solution
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