Answer:
a) 3000 Hz;
b) 30 dB;
c) 1000 times.
Explanation:
a) From the human audiogram given on the figure below the black line represents the threshold for hearing the sound at each frequency. We see that the least intensity is necessary for the frequency of about 3000 Hz.
b) Using the same audiogram we see that we would need the sound of the intensity of about 30dB.
c) The least perceptible sound at 1000 Hz must be 0dB while at 100 Hz it is 30dB. These are logarithmic quantities. To transform them to the linear quantities we use the formula
where 
is the hearing threshold at 1000 Hz.
Therefore we have the following
is the threshold at 1000Hz and 
is the threshold at 100Hz.
By exponentiating we have
Now dividing these two equations we get
Therefore, the least perceptible sound at 100Hz is 1000 times more intense than the least perceptible sound at 1000Hz.
Note: I got these values unisng the audiogram that is attached here. The one that you have might be slightly different and might yield different answers.
Answer:
6.2 ohm
Explanation:
Let R1 = 5 ohm
R2= 3 ohm
R3= 2 ohm
Since R3 and R2 are parallel then net resistance R' is given by
1/R' = 1/R2 + 1/R3
1/R' = 1/3 + 1/2
1/R' = 5/6
then
R' = 6/5 = 1.2 ohm
Now R1 and R' are in series, so
R = R1 + R'
R = 5 + 1.2
R = 6.2 ohm
Answer:
Answer: The height of the apple from the ground is at 49552.61071 m or is approximately at 5.0 × 10 m.
From Clausius theorem we get the formula for the change of entropy:
dS is the change of entropy, dQ is the change of energy, and T is the temperature in Kelvin.
We need to convert those temperatures:
Entropy changes inside and outside:
The net entropy increase is:
The heart rate that indicates your fitness level is the Resting Heart Rate.
<u>Explanation:</u>
The statement from Welch says that when we practise more and do an exercise harder, then the heart rate at rest would be low. This is the main reason for considering resting heart rates as a good indicator to one’s fitness level. The normal adult heart rate at rest is 60 to 100 bpm (beat per minute).
In general, a lower heart rate means a calmer heart rate and good heart health. For example, for a well-trained athlete, a normal heart rate can be closer to 40 bpm. Our resting rhythm, the measure of how often the heart beats every minute at rest.
