Solve the Problem $$e = 20 \sin \left( \frac { \pi t } { 4 } - \frac { \pi } { 2 } \right)$$

question 119

Multiple Choice

Solve the problem.
-A coil of wire rotating in a magnetic field induces a voltage given by
$$e = 20 \sin \left( \frac { \pi t } { 4 } - \frac { \pi } { 2 } \right)$$
where $t$ is time in seconds. Find the smallest positive time to produce a voltage of $10 \sqrt { 2 }$ .

• A) \(3 \mathrm { sec }\)
• B) \(3 \pi \mathrm { sec }\)
• C) \(2.8 \pi \mathrm { sec }\)
• D) \(2.8 \mathrm { sec }\)

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Definitions:

Marginal Tax Rate

The marginal tax rate is the rate at which the last dollar of income is taxed, reflecting the proportion of additional income that is paid in taxes.

Progressive Tax

A tax system where the tax rate increases as the taxable amount or income goes up, making it proportionately higher for wealthier individuals or entities.

Individual Income

The total earnings received by an individual from all sources, including wages, investments, and other forms of compensation.

Marginal Tax Rate

Refers to the rate at which the last dollar of income is taxed, indicating how much tax will be paid on an additional dollar of income.