Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric coaxial cable, assuming all other parameters are the same?
Foam dielectric coaxial cable has lower safe maximum operating voltage
Foam dielectric coaxial cable has lower loss per unit of length
Foam dielectric coaxial cable has higher velocity factor
All these choices are correct✓Correct answer
Explanation
Foam dielectric replaces much of the solid plastic with air: loss per unit length drops, velocity factor rises toward that of air, and the reduced amount of solid insulation lowers the voltage the cable can safely withstand. All three statements hold, so the combined answer is the correct one.