The energy associated with electric field is (Us) and with magnetic field is (UB) for an electromagnetic wave in free space. Then:
a.
UE = 
b.
c.
d.
a.
UE =
b.
c.
d.
Question ID - 50144 | SaraNextGen Top Answer The energy associated with electric field is (Us) and with magnetic field is (UB) for an electromagnetic wave in free space. Then:
a.
UE =
b.
c.
d.
The energy associated with electric field is (Us) and with magnetic field is (UB) for an electromagnetic wave in free space. Then:
|
a. |
UE = |
b. |
|
|
c. |
|
d. |
|
1 Answer
127 votes
Answer Key / Explanation : (c) -
Average energy density of magnetic field. UB=
, B0 is maximum value of magnetic field. Average energy density of electric field,
UE =
Now, 
UE =
=
UE = UB
Since energy density of electric & magnetic field is same, energy associated with equal volume will equal.
UE=UB
127 votes
Answer Link
127