Question

1.A cylinder of radius a = 7 cm and height h = 11.6 cm is aligned with its axis along the y-axis as shown. What is the total flux ? that passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

2.Another infinite line of charge with charge density ?2 = -14.7 ?C/cm parallel to the y-axis is now added at x = 3.5 cm as shown.

3.What is the new value for Ex(P), the x-component of the electric field at point P?

4.What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

5. The initial infinite line of charge is now moved so that it is parallel to the y-axis at x = -3.5cm.What is the new value for Ex(P), the x-component of the electric field at point P?

6. What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

Answer 1

1.A cylinder of radius a = 7 cm and height h = 11.6 cm is aligned with its axis along the y-axis as shown. What is the total flux ? that passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

flux = lambda1 h/epsilon0 = 4.9e-4*0.116/8.85e-12 = 6.4226e6 = 6.42 x 10^6 N.m2/C

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2.Another infinite line of charge with charge density ?2 = -14.7 ?C/cm parallel to the y-axis is now added at x = 3.5 cm as shown.

????

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3.What is the new value for Ex(P), the x-component of the electric field at point P?

Ex(P) = E1 - E2

Ex(P) = lamda1/(2 pi a epsilon0) - lamda2/(2 pi (a/2) epsilon0)

Ex(P) = (4.9e-4)/(2*3.1416*0.07*8.85e-12) - (14.7e-4)/(2*3.1416*(0.07/2)*8.85e-12)

Ex(P) = -6.29 x 10^8 N/C

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4.What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

flux = (q_net)/(epsilon0)

flux = (lambda1 + lambda2)*h/(epsilon0)

flux = (4.9e-4-14.7e-4)*0.116/(8.85e-12)

flux = -1.28 x 10^7 N.m2/C

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5. The initial infinite line of charge is now moved so that it is parallel to the y-axis at x = -3.5cm.What is the new value for Ex(P), the x-component of the electric field at point P?

Ex(P) = E1 - E2

Ex(P) = lamda1/(2 pi (3a/2) epsilon0) - lamda2/(2 pi (a/2) epsilon0)

Ex(P) = (4.9e-4)/(2*3.1416*(3*0.07/2)*8.85e-12) - (14.7e-4)/(2*3.1416*(0.07/2)*8.85e-12)

Ex(P) = -6.71 x 10^8 N/C

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6. What is the total flux ? that now passes through the cylindrical surface? Enter a positive number if

the net flux leaves the cylinder and a negative number if the net flux enters the cylnder.

flux = (q_net)/(epsilon0)

flux = (lambda1 + lambda2)*h/(epsilon0)

flux = (4.9e-4-14.7e-4)*0.116/(8.85e-12)

flux = -1.28 x 10^7 N.m2/C