Recent content by PhysicsinCalifornia

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    Solving Gauss's Law Problem for Electric Field

    There is actually a second and third part to this question: b) Find potentials at points in the regions: r_1 < a, a < r_2 < b, b < r_3 < c, and r_4 >c For r1 < a, I use the formula V_o - V_{r_1} = \int_0^r E(r_1)dr E(r_1) = \frac{\rho*r_1}{3\epsilon_o} V_o - V_{r_1} =...
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    Solving Gauss's Law Problem for Electric Field

    Homework Statement A uniformly charged ball of radius a and a total charge -Q is at the center of a hollow metal shell with inner radius b and outer radius c. The hollow sphere has a net charge +2Q. Find the magnitude of the electric field in the regions: r_1 < a, a < r_2 < b, b < r_3 < c, and...
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    Closest approach of particle problem - Please help

    Closest approach of particle problem - Please help! Homework Statement A proton (q = 1e, m = 1u) and an alpha particle (q = +2e, m = 4u) are fired directly toward each other from far away, each with a speed of 0.01c. What is their distance of closest approach, as measured between their...
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    Calculate Friction & Acceleration of 2.5kg Block on Horizontal Floor

    It helps to draw a FBD(free body diagram) of the block and write all the forces acting on it. I see 4 different forces, can you? (One of the force is at an angle, so that can be broken up into x and y components)
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    Why Did I Get the Newton's Law Problem Wrong?

    Well, I see that m_A + m_B comes from the two blocks on top of each other because block A is at rest relative to block B. In that case: T - f_k = (m_A + m_B)a T - \mu_kN = (m_A + m_B)a T - \mu_k(m_A + m_B)g = (m_A + m_B)a Plugging T with the equation that I had: T_c = m_cg - m_ca since...
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    Why Did I Get the Newton's Law Problem Wrong?

    Well, with my acceleration and your accerlation, I set those equal to each other and I got: m_c = \frac{(m_A + m_B)(\mu_s + \mu_k)}{(1 - \mu_s)}
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    Why Did I Get the Newton's Law Problem Wrong?

    Hi, I needed to calculate this for my quiz couple days ago, but I didn't get the right answer. Professor told me that I set it up correctly, so I don't understand why I got it wrong. Can anyone help? I resolved this problem, so I just need to verify the answer. Thanks Q: Block B, with mass...
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    Chem Rxn Help: Na_2SO_4 + Ba(NO_3)_2 -> BaSO_4 + NaNO_3

    I just needed help understanding the concept of this chemical reaction Na_2SO_4 (aq) + Ba(NO_3)_2 (aq) \rightarrow BaSO_4 (s) + 2NaNO_3 (aq) This is the conventional equation, and I wrote the net ionic form to be: SO_4^{2-} (aq) + Ba^{2+} (aq) \rightarrow BaSO_4 (s) However, the answer in...
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    Calorimetry Help: Solving a Problem with Ice Phase Change

    I needed to know if anyone can help me solve a problem. I am supposed to calculate the final temperature after mixing 250 mL of coffee at 80 degrees C with 250 g of ice at 0 degrees C. The heat of fusion for ice is 6.01 kJ/mol The ice undergoes a phase change, but I don't know how to...
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    Can anyone help me solve this?

    Dimethylglyoxime (DMG) is a carbon-hydrogen-nitrogen-oxygen compound with a molecular mass of 116.12 u. In a combustion analysis, a 2.464-g sample of DMG yields 3.735 g CO2 and 1.530 g H2O. In a separate experiment, the nitrogen in a 1.868 g sample of DMG is converted to NH3(g), and the NH3 is...
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    How much CO2 do humans produce through breathing?

    Sorry, I had another question, and that equation dealt with the previous question. I didn't know that I didn't have to use this equation for this problem. In that case, what is the first step to finding how much one person produces CO2 in one breath? I thought that PV=nRT was involved but I...
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    How much CO2 do humans produce through breathing?

    Did you use the equation C_8H_{18}(l) + O_2(g) \rightarrow CO_2(g) + H_2O(g)?
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    How much CO2 do humans produce through breathing?

    Hi, I have an assignment from my Chemistry class which is supposed to be done during my Spring break. The question is to CALCULATE the annual production of CO2(carbon dioxide) in metric tons by all humans in the world from breathing. The assumptions are: 1. The composition of exhaled breath...
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    Chemistry What is the Molecular Formula of Dieldrin?

    Sorry, the molecular formula is C_{12}H_8Cl_6O Thanks for the help
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    Chemistry What is the Molecular Formula of Dieldrin?

    Hey, I looked up the formula for dieldrin online. The molecular formula is C_{12}H_8Cl_8O www.chemfinder.com
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