For an incident wave which is normal on the perfect dielectric the reflection factor is given by (where 1 and 2 are the permittivities of 1st and 2nd medium respectively)

• A. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/191-116-1.png">
• B. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/191-116-2.png">
• C. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/191-116-3.png">
• D. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/191-116-4.png">