Recent content by blakester

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    What are the Work and Energy Relationships in a Spring System?

    hmm h = 6.51 is incorrect according to the website (also tried -6.51). i've been reading up on this physics site just trying to understand these problems. I've kind of given up on finishing my hmwk by midnight, but i do have a midterm tomorrow and I want to understand how this works so i still...
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    What are the Work and Energy Relationships in a Spring System?

    if i set the answer given from problems a and b equal to potential energy (mgh) i get some ridiculously small number. 10.994 / 700 / 9.8 = h = .00159 which seems impractical and is incorrect if i have Kei + Ui + W = kf + Uf where Kei, Ui, and kf all = 0 I'm left with W = Uf which gives me the...
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    What are the Work and Energy Relationships in a Spring System?

    i see, i guess i had my equation wrong. Well that gets me A and B but I'm having trouble figuring out how to get the second part. if H is 0 where you drop the block, would that make me use -mgh and set that equal to final potential energy (which i don't think i know)?
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    What are the Work and Energy Relationships in a Spring System?

    Homework Statement A 700 g block is released from rest at height h0 above a vertical spring with spring constant k = 380 N/m and negligible mass. The block sticks to the spring and momentarily stops after compressing the spring 24.0 cm. (a) How much work is done by the block on the...
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    One force represented along an x-axis

    ok i figured it out on my own and for anyone else wondering out there about this problem let me explain. using what i said in the before post ke=1/2mv^2 initial Ke + W = Ke final (which i'll call Kei and Kef now) at x=3 the work area added up under the line is 2 (at 0) 0 (at 1) -2 (at 2) and -4...
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    One force represented along an x-axis

    ok I'm just stabbing in the dark here but this is what i was thinking Ke=1/2mv^2 initial Ke + W = Ke final so if for part a x=3 and the force is -4 at that point work should be -12. the velocity at 0 is 4 m/s so initial kinetic energy is 19.2 19.2-12=7.2 kinetic energy at x=3
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    One force represented along an x-axis

    Homework Statement The only force acting on a 2.4 kg body as it moves along the x-axis varies as shown below. The velocity of the body at x = 0 is 4.0 m/s. (a) What is the kinetic energy of the body at x = 3.0 m? (b) At what value of x will the body have a kinetic energy of 8.0 J? (c) What...
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    Two blocks connected by string with an angled force applied

    oh man haha, why would i do that! thanks for looking it over i got it right now!
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    Two blocks connected by string with an angled force applied

    A 3.5 kg block (m1) and a 1 kg block (m2) are connected by a string and are pushed across a horizontal surface by a force applied to the 1 kg block as shown below. The coefficient of kinetic friction between the blocks and the horizontal surface is 0.3. If the magnitude of vector F is 27 N...
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    Just getting into friction kinetic and static

    Oh man such a simple mistake haha! Thanks alot, I'll be sure to double check my units on my midterm in a few hours
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    Just getting into friction kinetic and static

    The floor of a railroad flatcar is loaded with loose crates having a coefficient of static friction of 0.30 with the floor. If the train is initially moving at a speed of 43 km/h, in how short a distance can the train be stopped at constant acceleration without causing the crates to slide over...
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