Recent content by revere21

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    Work done by string, friction, pulling mass up an inclined plane

    In addition, two conceptual questions are asked of the problem. (1) Why is the work done on the block by the normal force zero? I believe this would be because the normal force of the block is equal to the weight, but I am not sure. (2) Imagine the string is now released. The block...
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    Work done by string, friction, pulling mass up an inclined plane

    Homework Statement A block of mass 1.60 kg is pulled up a rough 30 degree incline at constant speed by a string parallel to the surface. The friction force on the block is 7.00 N. The incline is 4.00 m long and 2.00 m high. (1) How much gravitational potential energy did the block gain...
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    Box dragged along floor at an angle, calculating normal and frictional force

    Awesome. Thank you, yet again. You, sir, are a freshman-level physics wizard.
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    Box dragged along floor at an angle, calculating normal and frictional force

    So, I take the horizontal component of 129.9 N, and the net horizontal force of 48 N, and plug it into F - f = ma? Is that right? That would give me 129.9 - f = 48, which comes out to f = 81.9 N. Can you give me one final hint and tell me if that is the right way to finish out this problem?
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    Box dragged along floor at an angle, calculating normal and frictional force

    The horizontal component would be 129.9 N, I believe. From using cos30 = adjacent/150. As far as a net horizontal force, where does this come from? Is it just Fhorizontal = 60*0.80 = 48?
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    Box dragged along floor at an angle, calculating normal and frictional force

    Homework Statement A 60 kg box is dragged along a rough but level floor by a rope at a 30o angle to the horizontal. The tension in the rope is 150 N, and the box is speeding up at 0.80 m/s2 (along the floor). (a) How large is the frictional force of the floor on the box? Homework...
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    Object thrown upward with known initial and final velocity

    Oh my goodness, thank you. Can't believe I didn't catch that one. Very, very simple problem, as it turns out. Thanks, SammyS. Awesome resource to have when my mind is fried from studying.
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    Object thrown upward with known initial and final velocity

    Okay, so the acceleration of gravity is 9.8 m/s2, which means that gravity causes an object to fall 9.8 meters per second, per second. Am I understanding the gist (sp?) of the point you are trying to convey? Still, in 3 seconds the gravity would have the object moving 3*9.8 = 29.4 m/s, which...
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    Object thrown upward with known initial and final velocity

    Yes, I understand that x(t) means x is a function of t. I didn't multiply the two together. My apologies for being unclear on that. But to answer your question, the velocity in the x-direction remains constant at 4.00 m/s throughout. So, for every second that passes the diver moves...
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    Object thrown upward with known initial and final velocity

    Homework Statement A cliff diver runs horizontally at 4.00 m/s. He hits the water 3.00 s later. Ignore air resistance. (a) What is the diver's speed (magnitude of the velocity vector) just before he hits the water? Homework Equations Change in y-component: y(t) = v[SIZE="1"]yot + (1/2)g(t^2)...
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