Subelement B: Electrical Math— Topic 9: Ohm’s Law-1
Question 3-9B5
Element 3 (GROL)If a current of 3 amperes flows through a resistor connected to 90 volts, what is the resistance?
Explanation
This question applies Ohm's Law, a fundamental principle in electronics and amateur radio theory. Ohm's Law describes the relationship between voltage (V), current (I), and resistance (R) in a circuit. It is typically expressed as V = I × R.
To find the resistance (R) when voltage and current are known, you can rearrange the formula to:
R = V / I
Plugging in the given values:
R = 90 volts / 3 amperes
R = 30 ohms
Therefore, a resistance of 30 ohms is required for 3 amperes to flow at 90 volts. Options A, C, and D are incorrect as they do not result from the correct application of Ohm's Law with the provided values.
Related Questions
3-9B3 If a current of 2 amperes flows through a 50-ohm resistor, what is the voltage across the resistor?3-9B4 If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor?3-9B6 A relay coil has 500 ohms resistance, and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 V DC?