Answer:
Explanation:
In the decibel scale , intensity of sound changes logarithmically as follows
Value in decibel scale , the value of I₀ = 10⁻¹² W /m².
Putting the values



W/m²
Similarly for 54 dB sound intensity can be given as follows
I = 10⁻¹² x 
W / m²
For intensity of sound the relation is as follows
I = 2π²υ²A²ρc where υ is frequency , A is amplitude , ρ is density of air and c is velocity of sound .
Putting the given values for 71 dB
= 2π² x 504²xA²x 1.21 x 346
A² = 60.03 x 10⁻¹⁶
A = 7.74 x 10⁻⁸ m
For 54 dB sound
= 2π² x 504²xA²x 1.21 x 346
A² = 1.1978 x 10⁻¹⁶
A = 1.1 x 10⁻⁸ m
Energy- the ability to do work/how things can change and move
Types
Potential Energy
Kinetic Energy
Nuclear Energy
Mechanical Energy
Sound Energy
Heat
Answer:If an object's speed changes, or if it changes the direction it's moving in,
then there must be forces acting on it. There is no other way for any of
these things to happen.
Once in a while, there may be a group of forces (two or more) acting on
an object, and the group of forces may turn out to be "balanced". When
that happens, the object's speed will remain constant, and ... if the speed
is not zero ... it will continue moving in a straight line. In that case, it's not
possible to tell by looking at it whether there are any forces acting on it
-- The sample was a fluid.
-- It was a mixture or a suspension ... NOT a solution.