ADVANTAGE
PEOPLE USED CERTAIN UNIT OF MEASUREMENT IN THEIR SPECIFIC REGION WHICH IS NOT ACCEPTED BY WORLD IN CGS SYSTEM.CGS UNIT MADE
DIFFICULTY IN TRADE. LATER SI UNIT OF MEASUREMENT HAVE BEEN ADOPTED IN 1960 AD TO BRING THE uniformity IN measurement throughout THE WORLD. SI SYSTEM MADE THE MEASURENT AROUND WORLD MORE EFFECTIVE AND LESS COFUSING THAN CGS UNIT.
I believe it is Acoustics, the real name for it would be like Reverberation. But go with Acoustics. :)
Complete question is;
A microwave oven operates at a frequency of 2400 MHz. The height of the oven cavity is 25 cm and the base measures 30 cm by 30 cm. Assume that microwave energy is generated uniformly on the upper surface of the cavity and propagates directly
downward toward the base. The base is lined with a material that completely absorbs microwave energy. The total microwave energy content of the cavity is 0.50 mJ.
Answer:
Power ≈ 600,000 W
Explanation:
We are given;
Frequency; f = 2400 Hz
height of the oven cavity; h = 25 cm = 0.25 m
base area; A = 30 cm by 30 cm = 0.3m × 0.3m = 0.09 m²
total microwave energy content of the cavity; E = 0.50 mJ = 0.5 × 10^(-3) J
We want to find the power output and we know that formula for power is;
P = workdone/time taken
Formula for time here is;
t = h/c
Where c is speed of light = 3 × 10^(8) m/s
Thus;
t = 0.25/(3 × 10^(8))
t = 8.333 × 10^(-10) s
Thus;
Power = (0.5 × 10^(-3))/(8.333 × 10^(-10))
Power ≈ 600,000 W