Calculate the actual intensity, Physics

The threshold of hearing is 10-12 watts/m2 or 0 dB.  How many times more intense than the threshold of hearing is 70dB and what is the actual intensity (in watts/m2) at the 70 dB level?  Show the physics.

Solution:

The threshold of hearing is assigned a sound level of 0 decibels (abbreviated 0 dB); this sound corresponds to an intensity of 1*10-12 W/m2.

A sound that is 10 times more intense ( 1*10-11 W/m2) is assigned a sound level of 10 dB. A sound that is 10*10 or 100 times more intense (1*10-10 W/m2) is assigned a sound level of 20 db. A sound that is 10*10*10 or 1000 times more intense (1*10-9 W/m2) is assigned a sound level of 30 db. A sound that is 10*10*10*10 or 10000 times more intense (1*10-8 W/m2) is assigned a sound level of 40 db.

Hence a sound that is 10 ^ 7  (10 to the power of 7) or 10000000 times more intense (1*10-5 W/m2) is assigned a sound level of 70 db.

 

Posted Date: 3/21/2013 5:59:53 AM | Location : United States







Related Discussions:- Calculate the actual intensity, Assignment Help, Ask Question on Calculate the actual intensity, Get Answer, Expert's Help, Calculate the actual intensity Discussions

Write discussion on Calculate the actual intensity
Your posts are moderated
Related Questions
Why different colours of white light travell with different speed in a glass prism,while they travell with same speed in air? Ans)Since in diffeernt medium frequecy remains const

Write two characteristic features of nuclear force which differentiate it from the Coulomb force.

What do you understand by "Absorption coefficient"? which is a better absorber of sound, glass or fibre glass?

The points of maximum amplitude are called as antinodes. At ends density and air pressure both are very low.

For the arrangement shown in Figure find (a) the equivalent capacitance of the circuit, (b) the voltage across QR, and (c) the charge on each capacitor

composition of mosfet .

A ring forming a magnetic circuit is made from two materials; one part is mild steel of mean length 25cm and cross-sectional area 4cm 2 , and the remainder is cast iron of mea

It is the ratio of the internal electric field induced by the charges on the surface on the dielectric when an external field applied to the polarization of the dielectric.


Explain quasi-static process The process in the system the variables (PTV) alters very slowly so that the systems remain in thermal and mechanical equilibrium with its surround