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Extra Credit Brown Bag

Due 9/5: Homework Chapter 5 # 55, 61, 78, 79, 80, 83, 84, 94, 97

Answers: 55)60nC, 61)5.11N(-j-hat), 78)SQRT(2)r1, 79)-2.8uC, 80)2.0x10^16m/s^2(j-hat), 83)kQ/[a(L+a)], 84)2k(lamda)/r, 94)1.2x10^(-3)m, 97){2k(lamda)/r}[-(i-hat)-(j-hat)]

Due 9/12: Homework Chapter 6 # 30, 48, 49, 50, 52, 53, 54, 68, 75, 89

Answers: 30) 0,-2q/eo,q/eo,-4q/eo,-2q/eo,3q/eo; 48)5.65x10^5N/C; 50)1.8x10^8N/C(-r-hat),0; 52)0,4.8N/C(r-hat),0,2.1N/C(r-hat),1.0N/C(r-hat); 53)rho*r/(2eo)(r-hat),pho*R^2/(2*r*eo)(r-hat); 54)alpha*r^2/(3eo)(r-hat),alpha*R^3/(3*r*eo)(r-hat); 68)4.0x10^(-6)C/m^2,4.5x10^5N/C(i-hat); 75)Eo(pi)R^2,0; 89)0, q1/(4*pi*eo*r^2)(r-hat), (q1+q2)/(4*pi*eo*r^2)(r-hat),0,q1,-q1,q1+q2.

Due 9/19: Homework Chapter 7 # 29, 30, 52, 56, 60, 70 (plates should have opposite sign), 77, 104, 105

Answers: 29)3.4J,2.4x10^4m/s; 30)471m/s; 52)7.5x10^8V,-3.8x10^9V,-9.0x10^8V,-9.0x10^8V; 56)(y^2z-4y)(i-hat)+(2xyz-4x)(j-hat)+xy^2(k-hat); 60)0,1.4MV,-kq1(1/0.05m-1/r),1.4MV,0; 70)4.4x10^15m/s^2; 77)1.9x10^6m/s,4.2x10^6m/s,5.9x10^6m/s,7.3x10^6m/s,8.4x10^6m/s; 104)4.1x10^16rad/s; 105)(i-hat),3.56x10^(-4)m,1.42x10^(-10)s,5.00x10^6m/s(-i-hat)

Due 9/26: Homework Ch 5 #118 and 125; Ch 6 #95; Ch 7 #101; Ch 8 #37, 53, 67, 69, 77, 78 parts (a) and (b)

Answers: 5-118)1.0x10^4N/C(i-hat)+1.9x10^4N/C(j-hat), 0.051N(i-hat)+0.093N(j-hat); 5-125)kq(lambda)*l/[a*SQRT(a^2+(l/2)^2)](j-hat); 6-95)q/(2*A*eo)(r-hat); 7-101)-6.78x10^5C,2.6x10^(13)m/s^2(r-hat), 2.4x10^(-18)kg; 8-37)11.4x10^(-6)F; 8-53)3.0V,0.60V,1.5x10^3V/m,300V/m; 8-67)0.065F,2.26x10^4C,4.0GJ; 8-69)75.6x10^(-6)C,10.8V; 8-77)89pF,6.1KV/m,4.5KV/m; 8-78)100V,150V.

Due 10/3: Homework Chapter 9 # 24, 30, 47, 61, 86, 88, 89 (find resistance in r-hat direction and in direction of long axis), 91 (for (d) assume all electrical energy converted to heat energy), 92 (look up wire radius on wikipedia)

Answers: 9-24)1.4C; 9-30)3.5A/m^2,3.7x10^7m/s,1.78x10^(-4)s; 9-47)2.4x10^(-8)ohm-m,112-ohms; 9-61)29%,4.0x10^(-5)%; 9-86)3.15x10^(-4)A; 9-88)-2.0A, -1.21A, 3.47s; 9-89)0.00251-ohms,0.20-ohms; 9-91)8.7A,2.5x10^(23)electrons,132-ohms,4.7x10^6J; 9-92)1.7A,10.5hours

Due 10/10: Homework Chapter 10 # 30, 38, 40, 50, 51 (part (a) 0.100x10(-6)seconds), 55, 72, 78, 90, 93

Answers: 10-30)0.4A,3.84W,15.36W,2.0A,0.5A,96W,24W; 10-38)3A,1A,18V; 10-40)1.5A,2.0A,0.5A; 10-50)3.3x10^7(ohms); 10-51)2.5x10^(-6)F,2.0s;10-55)10-microfarads,no; 10-78)2.0V,0.50V,1.50V; 10-90)9.99995A,1.25x10^(-3)V,1.25x10^(-4)ohms; 10-93)3800s,1.26mA,2633s.

Due 10/17: Homework Chapter 11 # 17, 34, 56, 83, 93, 104, 105, 106 (go by wording, not pic.), 108, 110

Answers:11-56)1.72x10^(-4)m; 11-83)0,0.12N(-i-hat) ; 11-93)2.8x10^(-8)V; 11-104)13.8degrees; 11-105)aIL^(2)/2(-j-hat); 11-106)wIB/(2k); 11-108)pi`Ir^(2)Bo*sin(theta); 11-110)0.025A`m^2(-k-hat),1.5x10^(-4)m`N(i-hat)+5.0x10^(-5)m`N(-j-hat)

Due 10/24: Homework Chapter 12 # 18, 31, 32, 34, 48, 65, 67, 76, 85, 90, 91 (find B at h, a vertical distance above the center of the spinning LP or CD disk)

Answers: 12-18)uoI(b-a)/(4ab)(k-hat); 12-31)(a)repel 2.0x10^(-5)N/m,(b)attract 2.0x10^(-5)N/m; 12-32)40A; 12-34)uoI1I2a/(4*pi*b)(-i-hat); 12-48)(a)uoIr/(2*pi*r1^2)cw,(b)uoI/(2*pi*r)cw,(c)uoI/(2*pi*r)(1-(r^2-r2^2)/(r3^2-r2^2))cw,(d)0; 12-65)1.4x10^(-4)T@240degrees; 12-67)3.2x10^(-19)N(j-hat); 12-76)4.2x10^(-9)T(k-hat); 12-85)(a)uoR^2Jo/(3r)ccw,(b)uoJor^2/(3R)ccw; 12-90)c/(2uo)((a2^2-a1^2)/b1^2+(a1^2-a2^2)/b2^2); 12-91)uo(omega)(sigma)/2((R^2+2h^2)/sqrt(R^2+h^2)-2h)(k-hat)

Due 11/7: Homework Chapter 13 # 30, 31, 35, 36, 45, 82 (assume constant speed)

Answers: 13-30)3.14x10^(-6)V; 13-31) -(C*b^2*a*(omega)/2)*cos((omega)t); 13-35) (a)150A down, (b) 46A up, (c)0.019A down; 13-36)(a)ccw,(b)ccw,(c)cw,(d)cw,(e)cw,(f)ccw; 13-45)0.018A cw; 13-82) RF/(B^2w^2)

Due 11/14: Homework Chapter 1 # 54, 74, 79, 81, 108, 116, 122, 123, 128

Answers: 1-54)21cm; 1-74)(a)2.5x10^6J,(b)1.4hrs; 1-79)(a)1.5x10^(15)kg,(b)4.9x10^(20)J,(c)48.5yrs; 1-81)(a)9.7L; 1-108)(a)2.8degreesC/s,(b)11.9min; 1-116)1450J/kg/C; 1-122)(a)3.9x10^(26)W,(b)6.7x10^8m; 1-128)(a)Is(pi)r^2,(b)0.7Is(pi)r^2,(c)255K.

Due 11/21: Homework Chapter 2 # 18, 31, 37, 46, 61, 64, 71, 74, 90

Answers: 2-18)1.64x10^5N/m^2; 2-31) (a)9.14x10^6N/m^2,(b)8.23x10^6N/m^2,(c)2.16K; 2-37)(a)5.88m/s,(b)5.89m/s; 2-46)1.58x10^5K; 2-61)3078J; 2-64)(a)72, 19, (b)5190J; 2-71)(a)417m/s,(b)471m/s,(c)511m/s; 2-74)chlorine gas; 2-90)21.6 degrees celcius

Due 11/28: Homework Chapter 3 # 28, 37, 41, 45, 46, 47, 57, 76, 84, 97

Answers: 3-28)(a)200J,(b)410J,(c)410J,(d)610J; 3-37)(a)610J,(b)0,(c)510J,(d)200J,(e)810J,(f)510J; 3-41)(a)600J,(b)600J,(c)810J; 3-45)(a)-150J,(b)-400J; 3-57)(a)700J,(b)500J; 3-76)(a)3.4x10^5Pa,260K, (b)4.0x10^5Pa,300K; 3-84)4500J; 3-97)(a)2.23 mol,(b)7.4x10^(-2)m^3,2.6x10^(-2)m^3,(c)1200K,430K,(d)30.5kJ

Due 12/5: Homework Chapter 4 # 41, 45, 46, 52, 61, 63

Answers: 4-41)(a)546K,(b)137K; 4-45)-13J/K/mol; 4-46)-61J/K; 4-52)(a)167J/K,(b)300J/K; 4-61)(a)1200J,(b)600J,(c)600J,(d)0.5; 4-63)nCvLN(T2/T1)+nCpLN(T3/T2)