A Small $4.0 - \mu C$ Charge and a Small $1.5 - \mu C$

question 36

Multiple Choice

A small $4.0 - \mu C$ charge and a small $1.5 - \mu C$ charge are initially very far apart. How much work does it take to bring them to a final configuration in which the $4.0 - \mu \mathrm { C }$ charge is at the point $x = 1.0$ $\mathrm { mm } , y = 1.0 \mathrm {~mm}$ , and the $1.5 - \mu \mathrm { C }$ charge is at the point $x = 1.0 \mathrm {~mm} , y = 3.0 \mathrm {~mm}$ ? $\left( k = 1 / 4 \pi \varepsilon _ { 0 } = 8.99 \right.$ $\times 10 ^ { 9 } \mathrm {~N} \cdot \mathrm { m } ^ { 2 } / \mathrm { C } ^ { 2 }$ )

• A) \(13.5 \mathrm {~kJ}\)
• B) \(27 \mathrm {~J}\)
• C) \(13.5 \mathrm {~J}\)
• D) \(54 \mathrm {~J}\)

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Definitions:

Renal Pelvis

The central collecting region in the kidney where urine gathers before moving into the ureter.

Minor Calyx

A cup-shaped structure in the kidney that encloses the apex of a renal pyramid and collects urine before it passes into the major calyx.

Collecting Duct

A series of tubules and ducts in the kidney that transport urine from the nephrons to the renal pelvis.

Ureter

A pair of tubes that carry urine from the kidneys to the bladder, facilitating the removal of waste from the body.