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What is the

direction of the

electric field at

the observation

location Adue to

piece 2?2

A

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What is the

direction of the

electric field at

the observation

location Adue to

piece 7?7

A

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What is the

direction of the

electric field at

the observation

location Adue

to the two

pieces 2 and 7? 72

A

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What is the

direction of the

electric field at

the observation

location Adue

to all eight

pieces? 72

A

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What is the

direction of the

electric field at

the observation

location Aif the

rod has a

uniform charge

of -Q?

72

A

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A rod of length L has

a uniform charge of

+Q. The rod is

divided into equal

pieces of length x

as shown. What is

the charge Q on one

slice?

1)QL/x2)Qx/L3)Q(L-x)/L4)2QL/x

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What are the

limits of

integration?

1)0 to 2)to +3)L to + L4)L/2 to +L/25)0 to L

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Which will give

us a more

exact result:

1)Dividing the rod into a few slices and adding upthe electric field of each slice by hand.

2)Dividing the rod into many slices and adding upthe electric field of each slice using a computer.

3)Dividing the rod into infinitesimally small slicesand adding the electric field of each slice using

integration.

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Q15.1aHere is a rod lying on the y axis. It is

uniformly charged positive.

What is the direction of the net

electric field at location A?

A

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Q15.4aUniformly charged ring of charge Q andradius R

What is Q, expressed in terms ofgiven constants and an integrationvariable?

1) Q /

2) Q/ (2R)3) Q* / (2R)

4) Q* / 2

5) Q*R*/(2R)

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Q15.4bUniformly charged ring of charge Q andradius R

What are the integration limits?

1) 0 to

2) to +3) 0 to

4) 0 to2

5) 2to +2

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Q15.4cBy thinking about the physicalsituation, predict the magnitude ofthe electric field at the center of auniformly charged ring of radius Rcarrying a charge +Q. Then use theformula we just derived to confirm

this result.

1) E = 1/(40) Q/z2

2) E = 1/(40) Qz/R3

3) E = 0

4) E =

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Q15.7aThe electric field at any location inside a hollow, uniformly charged sphere,due to the charge on the surface of the sphere, is zero. True or false?

1) True, because the electric field can't penetrate the material of the sphere2) True, because the contributions of all the charges on the surface add up

to zero at every location inside the sphere.

3) True, but only at the center of the sphere, where all the contributions cancel.4) False, because the electric field due to the surface charges penetrates

the sphere.