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#
1.5 volts sent through a 20 KΩ resistor would result in

8
0
0

`____`

of current.
A
0.075 milliamperes
*I*, and substitute the known values, noting that 20k ohms is equivalent to 20,000 ohms: I = 1.5V/20,000ohms.

This yields an answer of amperes, but the answer choices only provide milliamperes. To convert amperes to milliamperes, use the conversion factor of 1 A = 1000 mA: 0.000075A x (1000 mA/1A) = 0.075 mA.

Note that the A's in the numerator and denominator cancel, leaving the desired mA; this technique is called dimensional analysis and proves extremely useful in verifying answers.

Explaination

Ohm's Law states that voltage is equal to current times resistance, or, V = IR. Solve the equation for current, This yields an answer of amperes, but the answer choices only provide milliamperes. To convert amperes to milliamperes, use the conversion factor of 1 A = 1000 mA: 0.000075A x (1000 mA/1A) = 0.075 mA.

Note that the A's in the numerator and denominator cancel, leaving the desired mA; this technique is called dimensional analysis and proves extremely useful in verifying answers.

B 7.5 milliamperes

C 75 milliamperes

D 0.000075 milliamperes

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