Answer:
100 iPods
Explanation:
The deciBell scale is logarithmic, and thus, it turns multiplying into adding.
Initially, it was the Bell scale, purely logarithmic, where "times 10" is translated into "plus 1" (just like normal logs). However, the steps became too big and so they divided the Bell in 10 parts, the deciBell.
The levels above could well have been called 10B and 12B.
Usually, we define the dB scale for intensity as:
I(dB) = 10•log(I)
Thus,
I = 10^(I(dB)/10)
Now 120 dB gives us units of I = 10^(120/10) = 10^12 Pa (assume the dB are measured to 1 Pa) and 100 dB is 10^10 Pa.
Thus, we would need 100 ipods to get the same intensity
Answer:
Change in momentum is zero.
Explanation:
The following data were obtained from the question:
Mass (m) = 5000 kg
Time (t) = 1 h
Net force (F) = 0
Change in momentum =?
Force = Rate of change of momentum
0 = change in momentum
Change in momentum = 0
We can see from the above illustration that the net force is zero. Thus, the change in momentum is also zero.
All vehicles are required to stop within 15 FEET of the railroad crossing when a train is approaching.
Answer:
Option (A) is correct.
Explanation:
A horizontal rope has a length of 5 m and a mass of 0.00145 kg. If a pulse occurs on this string, generating a wavelength of 0.6 m and a frequency of 120 Hz. The tension to which the string is subjected is
mass of string, m = 0.00145 kg
Frequency, f = 120 Hz
wavelength = 0.6 m
Speed = frequency x wavelength
speed = 120 x 0.6 = 72 m/s
Let the tension is T.
Use the formula
Option (A) is correct.
The ratio of output force to the input force is generally the mechanical advantage of the machine.
