[amp_mcq option1=”Speed of light” option2=”Radio wave frequency” option3=”Intensity of sound” option4=”Intensity of heat” correct=”option3″]
The correct answer is C. Intensity of sound.
Decibel (dB) is a logarithmic unit that expresses the ratio of a physical quantity (such as sound pressure, power, voltage, etc.) to a reference value. It is often used to express the intensity of sound, which is the amount of energy per unit area that is carried by a sound wave. The intensity of sound is measured in decibels (dB), with 0 dB being the threshold of human hearing. A sound that is 10 dB louder than another sound is twice as intense, and a sound that is 20 dB louder is four times as intense.
The other options are incorrect because:
- Option A: Speed of light is measured in meters per second (m/s).
- Option B: Radio wave frequency is measured in hertz (Hz).
- Option D: Intensity of heat is measured in joules per second per square meter (J/s/m2).