Answer:
(a) The magnetic energy density in the field is 6.366 J/m³
(b) The energy stored in the magnetic field within the solenoid is 5 kJ
Explanation:
magnitude of magnetic field inside solenoid, B = 4 T
inner diameter of solenoid, d = 6.2 cm
inner radius of the solenoid, r = 3.1 cm = 0.031 m
length of solenoid, L = 26 cm = 0.26 m
(a) The magnetic energy density in the field is given by;

(b) The energy stored in the magnetic field within the solenoid


Complete question:
A light bulb emits light that travels uniformly in all directions. Detailed measurements show that at a distance of 56 m from the bulb, the amplitude of the electric field is 3.78 V/m. What is the average intensity of the light?
Answer:
The average intensity of the light is 0.02 W/m²
Explanation:
Given;
Amplitude of the electric field, E₀ = 3.78 V/m
The average intensity of the light is calculated as follows;

where;
is the average intensity of the light
c is speed of light = 3 x 10⁸ m/s

Therefore, the average intensity of the light is 0.02 W/m²
Answer:
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