Energy Density: The energy density of an electromagnetic wave in free space is
A. entirely in the electric field.
B. entirely in the magnetic field.
C. 1/4 in the electric field and 3/4 in the magnetic field.
D. 1/4 in the magnetic field and 3/4 in the electric field.
E. equally divided between the magnetic and the electric fields.
Answer: E
You might also like to view...
A 5-kg piece of lead (specific heat 0.03 cal/g/°C) having a temperature of 80°C is added to 500 g of water having a temperature of 20°C. What is the final equilibrium temperature (in °C) of the system?
a. 79 b. 26 c. 54 d. 34 e. 20
Main sequence stars are fusing hydrogen into helium in their cores
Indicate whether the statement is true or false
Evaporator tubes in a refrigerator are constructed of 1 inch OD aluminum tubing with 1/8 in thick walls. The air surrounding the tubing is at 25ºF and the refrigerant in the evaporator is at 15ºF. Estimate the heat transfer to the refrigerant over 1 foot of length.
What will be an ideal response?
Two wires, each carrying current I, are antiparallel to each other. The two wires
A. repel each other. B. attract each other. C. are not affected by each other.