Lista 2 Gabarito 2015 2 Fisica 2 Uff

1) a) I = I_1 | I_2 | b) i = I / A | i > I_2 I | c) \sigma = \varepsilon_4 \gamma e_2 | d) \gamma = m \varepsilon u_d \quad v_d > v_2 2) \Delta V = E / I \to I = \Delta V / R \quad I = 2 / R \frac{\omega}{100} \to R = 50 \Omega 3) a) I = E / R \quad q = I + q = 0.5 \times 10^6 \quad q = ne \quad N = I / e = 0.5 \times 10^6 / 1.6 \times 10^{-19} = 3.1 \times 10^{8} electrons b) j = I / A = 0.5 \times 10^{-6} = q / t = 4.0 A / m^2 c) e \Delta V = \frac{1}{2} m v^2 \Delta V = m v^2 / e 2 = \frac{9.1 \times 10^{-31} \times 10 \times 10^6}{2 \times 1.6 \times 10^{-19}} \Delta V = 9 \times 10^5 = 9.6 \times 10^5 V E = \Delta V / d = 4.6 \times 10^5 / 5 \times 10^{-3} = 9.1 \times 10^8 \frac{V}{m} d) E_c = c \Delta V = 1.6 \times 10^{-19} \times 4.6 \times 10^5 = 7.4 \times 10^{-14} J P = N E_c = 3.4 \times 10^7 \times 7.4 \times 10^{-16} = 2.3 \times 10^{-3} W 4) A \mathrm{l\acute{a}mpada} \to \B \quad \text{apagada} A \mathrm{l\acute{a}mpada} \to \A \quad \text{\acute{a}ilumina} \text{o brilho} 05) E - R j = 0 \quad r = E / I = 1.5 / 2 = 0.655 \Omega P = \Delta V / IE = 0.65(1.5 / 3) = 3.4 \mu 6) \frac{1}{R_4} + \frac{1}{R_6} + \frac{1}{R_5} + \frac{1}{R_6} = 45.5 / 47.5 = 47 /45 = 48 \Omega R_e = 42 \times R_6 = 47 \times 39 = 60 \Omega \quad \frac{1}{R_e} + 40 = \frac{1}{36} + \frac{1}{45} + \frac{1}{60} = 1 + 7 / 45 \quad = \frac{7}{45} \cdot 7 \omega 07) V_d = 0 \quad V_A = V_d + q - 9 V \quad V_B = V_d - 2 I = 9 - 2 \to 7 V \quad V_C = V_d - 6 = 7 - 6 = 1 V 08) \quad q_o = C \Delta V = 4 \times 10^{-6} \times 9 = 36 \times 10^{-6} C = 36 \mu C a) q = 36 \mu C \quad \Delta v = 9 V \Delta V_R = IR \to I = \frac{9}{20} \to 0.36 A b) q_(t) = q_o e^{-t/ RC} \quad Z_c = R C = 25 + 4 \times 10^{-6} = 100 ms \quad q (100 ms) = 36 \times 10^{-6} e^{-500} = 36 \times 10^{-6} e^{-\frac{12}{3}} = 2 \times 9 C \quad = 10 \mu C I(t) = I_o e^{-t / RC} = -0.36 e^{-t / R 2t} = 0.20 A 09) \quad q (200 \mu F) = 36 \times 10^{-6} e^{-\frac{20}{1000}} = 9.9 \times 10^{-5} = 19 \mu C (100 ms) \cdot = 0.049 \mu 9) I = I_1 + I_2 \quad P = RI^2 \quad I_2 = \frac{E}{2R} \frac{P_{B} \quad e - R^2}{P_{I R}} = \frac{e^2}{4 R} = P_B \frac{1}{R_{2}} = \frac{4}{5} \cdot 1 + \frac{1}{3} = PE = 0.15_e \frac{P_{A}}{P_{c}} = \left( \frac{I}{2} \right)_p \frac{P_{2}}{P_I_{3}} 10) \mathbb{E} - e R I = 0 \quad I = \frac{E}{r + R} \quad I = \frac{E}{5} \quad I = \frac{E}{2e^{2}t } + \varepsilon = 6 \times 10 = 60 V 11) \quad q - 3 I - 3.2 = 0 \quad I_A = 1 A I = I_1 I_2 \quad I_2 = 2A \varepsilon = 2 \times 4.5 - 2 \times 3 = 0 \quad \boxed{\varepsilon = 15 V} 12) VA = RI = 50 x 50 x 10^-6 = 2500 x 10^-6 a) VA = 25 mV VR = RI => 25 x 10^-3 = R 49,5 x 10^-3 R = 25/49,5 = 0,5 \Omega b) \frac{1}{Re} = \frac{1}{50} = \frac{1}{0,5} Re = 0,50 \Omega 13) dB = \frac{\mu_0 i}{4\pi} \frac{dl \times \hat{r}}{ Se revierte porque la espira se comporta como un imán norte/sur 14) F = e(\vec{i} + \vec{j}) F = (e^(-u/t^1) x (0,5)\vec{j} = 0 15) I = \frac{V}{R} = \frac{15}{7} = 5 A F = \int \iota B = 5 x 10 x 0.5 x 10 = 0.5 N 16) \tau = \vec{\mu} \cdot \vec{B} a) \tau = M \cdot B AB = IE \cdot A \mu_0 IE = 0,2 \pi (r^2) \frac{4\pi x 10^-7}{2\pi} = 0,4 \pi x 10^-3 b) \hat{\mu}\hat{\tau} 17) B = \frac{\mu_0 i}{2\pi r} a) I = \frac{E}{R} = \frac{9}{1} = 9A b) I = 0 L\Rightarrow B = 0 18) \oint \vec{B} \cdot d\ell \oint B \cdot d\vec{\ell} en toda superficie \oint \vec{B} \cdot d\ell = \oint \quad El force de \phi B \cdot d\ell = B \cdot 2\pi \tau \quad B\cdot 2\pi \tau = \frac{\mu_0 i}{r} B = \frac{\mu_0 i}{2\pi R} a) R_4 = \frac{R_2}{3}\quad r= \frac{R_2}{3} 19)(1) Campo de fuerza \quad B\quad da pola B2g = \frac{\mu_0 i}{\pi d} 20) B\cdot d\ell = \int B \cdot d\vec{\ell} = AB = \frac{\mu_0}{2\pi d} F = q \cdot V \times B B_p = \frac{\mu_0 i}{2\pi d} - f_{STF} B_{PQ} = B_{up} + \frac{\mu_0}{\pi d} B_{p} \left(-\mu_{o}I_{1} + \frac{4I_{1}}{4\pi d} - \frac{\mu_{o}I}{2\pi d}\right) \hat{j} = \left( \frac{-2\mu_{o}I + 3\mu_{o} - 6\mu_{o}I}{12\pi d} \right) \hat{j} = \left( \frac{-5\mu_{o}I}{12\pi d} \right) \hat{j} \begin{vmatrix} B_{1} = \frac{5\mu_{o}I}{12\pi d} \hat{j} \end{vmatrix} \begin{pmatrix} 2d \end{pmatrix} bp_{a} S \longrightarrow\text{N}^\left. \begin{pmatrix}\begin{array} \, 6-4-1 \end{array} 2 \end{pmatrix} \begin{array}\, 7-2 \end{array} 3 \end{pmatrix} \begin{array}\, S-\text{N}\text{N}-S-\text{N}\begin{pmatrix}\begin{array}\begin{array}\, OS \begin{array}\ \text{E}\begin{array}\ \text{AISES TEND- A SE APROXI} \end{array}