Recent content by mlb2358

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    The Pressure at the Bottom of a Container

    Homework Statement My physics textbook states that the pressure at some point in a fluid filled container a distance h below the fluid air interface is dependent only upon h, the density of the fluid, and the acceleration due to gravity. If this is the case, then the pressure at the bottom of...
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    Equilibrium Question involving Torque

    Thanks, I didn't realize that until you mentioned it. Also, just to be clear, the point of application moves to the right so that the length of the lever arm decreases and thus the magnitude of the torque produced by the normal force can be minimized. I guess its also interesting to note that as...
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    Equilibrium Question involving Torque

    I see now. The ground exerts a normal force at the right end of the body of the crane. The normal force can be found by finding the net force in the y direction and equating it to 0. This gives the correct answer. As for the torque exerted by the crane arm, no separate information is given for...
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    Equilibrium Question involving Torque

    Thanks for the reply. I guess the ground would exert a normal force on the crane, but wouldn't this simply be equal and opposite to the weight of the crane? If not, then I'm really not sure how to incorporate it.
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    Equilibrium Question involving Torque

    Homework Statement The crane shown below has a mass of 4000 kg and a base of 3.4 m. The arm of the crane is 22 m and attaches to the center of the crane. If the arm is placed at an angle of 30°, what is the largest mass that the crane can hold off the ground without tipping? Homework...
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    Translational and Rotational Equilibrium

    I apologize for not using the guidelines. I haven't been on this forum in some time and was using a mobile device to post my question. In response to the question, the requirement is that the vector sum of all of the forces acting on the system should be equal to 0. From dauto's response I...
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    Translational and Rotational Equilibrium

    The center of mass of the system would be the center of the rod which does accelerate. Does this mean that we can only have translational equilibrium while not having rotational equilibrium when the fulcrum is at the center of mass of the system? Also, the question asks specifically whether the...
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    Translational and Rotational Equilibrium

    Hi Everyone, I'm having some trouble with a problem concerning translational and rotational equilibrium. The question involves a balance with various masses suspended from it (see attached image). The question states that the counterweight is moved from 1cm away from the fulcrum to 2cm away from...
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    Finding the Time Constant in a circuit

    Homework Statement Find the time constant in the following circuit when switch K1 is open. R1 = 100 Ohms R2 = 200 Ohms C1 = 6 micro Farads E1 = 9V Homework Equations T = RC The Attempt at a Solution When the resistors are in series or parallel, I am clear on how to do this...
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    Spanning Sets in Vector Spaces

    Homework Statement True or False: If S is a spanning set for a vector space V, then every vector v in V must be uniquely expressible as a linear combination of the vectors in S. Homework Equations The Attempt at a Solution For some reason, the answer to this question is false...
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    Power generated by water flowing over a dam

    Homework Statement The Grand Coulee Dam is 1270 m long and 170 m high. The electrical power output from generators at its base is approximately 2000 MW. How many cubic meters of water must flow from the top of the dam per second to produce this amount ofpower if 92% of the work done on the...
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    Stoke's Theorem Question with plane and sphere

    I thought that by Stoke's Theorem ∫F·dr = ∫∫(∇xF)dS, which means that if I take the curl of F, I can use the surface instead of the boundary.
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    Stoke's Theorem Question with plane and sphere

    Homework Statement Let F =< yz + x, xz + 2x, xy + 3x >. Evaluate ∫F·dr where C is the intersection of the plane 2x + y − 3z = 0 and the sphere x2+ y2 + z2 = 4 oriented positively when viewed from above. Homework Equations The Attempt at a Solution The main question I have about...
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    Applying Stoke's Theorem to a parabaloid

    Homework Statement Let S be the surface defined by y=10−x^2−z^2 with y≥1, oriented with rightward-pointing normal. Let F=(2xyz+5z)i+e^(x)cosyzj+(x^2)yk. Determine ∫∫∇×F·dS. Homework Equations ∫∫∇×F·dS = ∫F·dS The Attempt at a Solution I think the boundary of the surface is the...
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    Question involving Newton's laws

    Thanks for the reply. I didn't list a mass because the question didn't provide one. The answer is expected to be in terms of mg. The answer is supposed to be 1.22mg, but I am getting an answer of .82mg.
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