🔍 Key Concepts
• Relationship between radiated field strength and antenna current in basic radio theory
• How power, current, and field intensity relate (think in terms of proportional vs. proportional to the square)
• Difference between something being proportional to a value vs. proportional to the square of that value
💭 Think About
• If you double the antenna current, what happens to the field intensity according to each of the options? Work through each choice logically.
• Think about how radiated power from an antenna changes with current. Then, how does field intensity (E-field at some distance) relate to that power?
• Compare this to familiar electrical relationships: for a resistor, how does power relate to current? Is field intensity more like current itself, voltage, or power?
✅ Before You Answer
• Be clear on the difference between field intensity (E-field strength) and power (Poynting vector / watts). They are not the same quantity.
• Check the mathematical form: when a quantity is said to be directly proportional, doubling one exactly doubles the other. For square relationships, doubling one causes a factor of four change in the other.
• Verify which quantity in antenna theory is proportional to I, and which is proportional to I² (current squared).