Answer:
dβ = 70. 77 dβ
Explanation:
The intensity of sound in decibels is
dβ = 10 log I/I₀
let's look for the intensity of this signal
I / I₀ = 10 dβ/10
I / I₀ = 3.981 10⁶
the threshold intensity of sound for humans is I₀ = 1 10⁻¹² W / m²
I = 3.981 10 ⁶ 1 10⁻¹²
I = 3,981 10⁻⁶ W / m²
It is indicated that 3 cornets are placed in the circle, for which total intensity is
I_total - 3 I
I_total = 3 3,981 10⁻⁶
I_total = 11,943 10⁻⁶ W / m²
let's reduce to decibels
dβ = 10 log (11,943 10⁻⁶/1 10⁻¹²)
dβ = 10 7.077
dβ = 70. 77 dβ
I would say…
B) they have many current paths
Multiply it by a fraction equal to ' 1 ', like this:
(14.8 cm) x (1 meter/100 cm) = 14.8/100 = 0.148 meter
4, 1, 3, 2 ??
I think that’s right
Equal the tension of the line to the force needed to stop (deselerate) the mass from a speed of 9.2 ft/s to 0 in 4.4 inches.
Start converting all the information to the SI.
mass, m = 19 lb * [1kg/2.2046lb] = 8.618 kg
speed: 9.2 ft/s * .3048m/ft = .2.80 m/s
distance to stop: 4.4 in * [2.54cm/in]*[1m/100cm] = 0.11176 m
constant acceleration => Vf^2 = Vo^2 - 2ad
Vf = 0 => a= V0^2 / 2d = [2.80m/s]^2 / (2*0.11176m) = 35.1 m/s^2
Use the second Law of Newton
Net force = m*a = 8.618 kg * 35.1 m/s^2 = 302.5 N
Answer: 302.5 N
