Answer:
Explanation:
A fire alarm notification appliance is an active fire protection component of a fire alarm system. The primary function of the notification appliance is to alert persons at risk.
If want the audible public mode signal to be hear clearly then, we need to have a sound level that is at least 15dB above the average ambient sound level or 5dB above the maximum sound level of at least 1minute
In this case the,
The average ambient sound level is 62dB,
And the maximum sound level is 68dB
Then, the public mode signal should be at least
1. 62dB+ 15dB=77dB
Or
2. 68dB +5dB =73dB.
Then the public mode signal hearing must be at least 77dB.
Asteroids do this because of Newton's Third Law. When a asteroid hits something, it will keep on moving (spinning) until it hits something else.
Electrons on the outermost shell/energy level
Answer:
Explanation:
a )
The Gaussian surface must have contained both the charges like +3 nC and - 3 nC , total charges being zero . According the Gauss's law , total electric flux over a closed surface is equal to 1 / ε₀ times the total charge contained inside the closed surface .
Since total charge inside is zero , total flux will be 1 / ε₀ x 0 = 0
b )
In this case the Gaussian surface is so small that it contains only the charge
+ 3 nC .
So electric flux over the Gaussian surface
= ( 1 / ε₀ ) x 3 x 10⁻⁹
= (1 / 8.85 x 10⁻¹² ) x 3 x 10⁻⁹
= 3 x 10³ / 8.85
= 339 weber.
=
