The unit measurement for sound can be expressed in terms of intensity and in decibels. The intensity of sound is the measure of its power over unit area. The common unit of measurement is in decibels. This is commonly used in measuring the extent of noise. The conversion from intensity to the decibel unit is through logarithmic function. The formula is:
dB = 10 log(I/I0), where I0 is 10^-12 Watts per square meter
Substituting the values to the equation,
84 = 10log(I/10^-12)
I = 0.0002512 W/m2
In scientific notation the intensity is 2.512 x 10^-4 W/m^2.
The answer would be energy, because all wave emitters give off at least one type of energy....
The correct answer to this question is this one: B. 5.89 feet
<span>The area of a circular trampoline is 108.94 square feet. The radius of the trampoline is 5.89 feet.
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For a circle,
A = (pi)r^2
108.94 ft^2 = (pi)r^2
r^2 = (108.94 ft^2)/(pi)
r = sqrt(108.94/pi) ft
r = 5. 89 ft
Answer:
A. the magnitude of the force between the spheres is 3.97 x 10⁻⁴ N
B. the magnitude of its initial acceleration is 5.83 m/s²
Explanation:
given information:
metal sphere's mass, m = 0.1 g = 1 x 10⁻⁴ kg
charge, q = -21 nC = -2.1 x 10⁻⁸
r = 10 cm = 0.1 m
What is the magnitude of the force between the spheres?
F₁₂ = k q₁q₂/r²
= ( 9 x 10⁹) (-2.1 x 10⁻⁸)²/(0.1)²
= 3.97 x 10⁻⁴ N
If the upper sphere is released, it will begin to fall. What is the magnitude of its initial acceleration?
mg - F₁₂ = ma
a = g - (F₁₂/m)
= 9.8 - (3.97 x 10⁻⁴/1 x 10⁻⁴)
= 5.83 m/s²
Answer:

Explanation:
The relationship between the refractive index and the critical angle is given as follows:

where,
η = refractive index = 1.67
θc = critical angle =?
Therefore,

