An Electron Moves with a Speed Of $8.0 \times 10 ^ { 6 } \mathrm {~m} / \mathrm { s }$

question 17

Multiple Choice

An electron moves with a speed of $8.0 \times 10 ^ { 6 } \mathrm {~m} / \mathrm { s }$ along the $+ x$ -axis. It enters a region where there is a magnetic field of $2.5 \mathrm {~T}$ , directed at an angle of $60 ^ { \circ }$ to the $+ x$ -axis and lying in the $x y$ -plane.
Calculate the magnitude of the acceleration of the electron. $\left( e = 1.60 \times 10 ^ { - 19 } \mathrm { C } , m _ { e 1 } = 9.11 \times 10 ^ { - 31 } \right.$ $\mathrm { kg }$ )

• A) \(1.3 \times 10 ^ { 18 } \mathrm {~m} / \mathrm { s } ^ { 2 }\)
• B) \(3.0 \times 10 ^ { 18 } \mathrm {~m} / \mathrm { s } ^ { 2 }\)
• C) \(0 \mathrm {~m} / \mathrm { s } ^ { 2 }\)
• D) \(1.3 \times 10 ^ { - 18 } \mathrm {~m} / \mathrm { s } ^ { 2 }\)
• E) \(3.0 \times 10 ^ { - 18 } \mathrm {~m} / \mathrm { s } ^ { 2 }\)

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Definitions:

Straight-line Method

A method of calculating depreciation for an asset that spreads the cost evenly over its useful life.

Accumulated Depreciation

The total amount of depreciation expense that has been recorded for an asset over its useful life, reducing its book value.

Salvage Value

The estimated residual value of an asset at the end of its useful life, reflecting what it could be sold for or scrapped for parts.

Journal Entries

Journal entries are the basic means of recording financial transactions in the accounting system, consisting of debits and credits.