Recent content by cassienoelle

  1. C

    Find mass using acceleration and tension

    I did draw that's what I just said. " so. My FBD looks like: T upwards with A And Weight downwards, so mg. so T+A = mg but, that didn't work either "
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    Object hangs from rope on a railroad car

    Other than gravity? Um, the acceleration. That's all I can think of. And the mass of the ball.
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    Object hangs from rope on a railroad car

    so gravity is in the vertical direction down. and acceleration is in the horizontal direction straight to the right and mass is at angle theta from the y axis?
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    Two masses, frictionless pulley

    Okay so: MEi = MEf m1=8.7 hi=1.09 hf = 0 m2 = 3.9 hi = 0 hf = ? KEi + PEi = KEf + PEf 1/2mv^2 + mgh = 1/2mv^2 + mgh (1/2)(m??1 or 2??) V^2 + m?g0 = 1/2 m? 0 + mgh
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    Find mass using acceleration and tension

    so. My FBD looks like: T upwards with A And Weight downwards, so mg. so T+A = mg but, that didn't work either
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    Object hangs from rope on a railroad car

    No one is helping. I have NO IDEA WHAT I'M DOING. I don't understand physics. I don't understand gravity. I DON'T UNDERSTAND ANY OF THIS.
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    Two masses, frictionless pulley

    i'm stuck. period. i have NO idea where to even start.
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    Two masses, frictionless pulley

    Homework Statement Two masses are connected by a light string that goes over a light, frictionless pulley, as shown in the figure. The 8.7-kg mass m1 is released and falls through a vertical distance of h = 1.09 m before hitting the ground. Use conservation of mechanical energy to determine...
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    Object hangs from rope on a railroad car

    Homework Statement A 7.3 kg object hangs at one end of a rope that is attached to a support on a railroad car. When the car accelerates to the right, the rope makes an angle of 7.8 degrees with the vertical, as shown in the figure below. (attached) What is the acceleration of the...
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    Find mass using acceleration and tension

    Homework Statement A box is raised using a rope. If the acceleration of the box, is 5.2 m/s2 (upward) and the tension in the rope is 58 N, what is the mass of the box (in kg)? Homework Equations The Attempt at a Solution I thought T=ma would work, but yeah, it didn't.
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    Given acceleration and velocity; find length

    Homework Statement An aircraft takes off at 213 km/h after accelerating from rest at 2.86 m/s2. What is the minimum runway length required? Homework Equations The Attempt at a Solution I know it's super simple, but I can't figure it out. I know I have to convert 213km/hr to m/s...
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    Mass Sliding at An Angle; find mass of one

    So if M2: T-mg=ma Then T-(4.5)(9.81) = (4.5)(3.09) Then T=58.05 ? And if M1: mgsin20+u-T = ma then m(9.81)(sin20) + .450 - 58.05 = 3.09m so m = 217.35kg but the homework says that's not right.
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    Two Masses Connected by Pulley; find acceleration

    okay. i guess i just don't understand how to get the equations.
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    Two Masses Connected by Pulley; find acceleration

    Okay. And w = mg F = ma now what?
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    Two Masses Connected by Pulley; find acceleration

    M1 T - m1*g = m1*a M2 T + m2*g = m2*a ?