Explanation:
Loudness of sound is a measure of response of sound to our ear. Loudness of sound is not simply the energy reaching the human ear, but it also tells about the sensitivity of human ear detecting this energy. Loudness of sound is measured in decibel (dB). As energy reaching the ear depends on square of amplitude, loudness of sound depends on various factors namely,
(i) Amplitude of sound waves
(ii) Sensitivity of ear
(iii) Distance from the source of the sound and the listener.
Power is the energy in a system per time. It will have units of Watts which is equal to joules per second. It can be expressed as:
P = E / t
where E = Force x distance
P = Fd / t
t = Fd / P
t = 8 (9.72) / 3.0
t = 25.92 s
Answer:

Explanation:
using the law of the conservation of energy:


where K is the spring constant, x is the spring compression, N is the normal force of the block,
is the coefficiet of kinetic friction and d is the distance.
Also, by laws of newton, N is calculated by:
N = mg
N = 3.35 kg * 9.81 m/s
N = 32.8635
So, Replacing values on the first equation, we get:

solving for
:
