Cause: sewage dumped in rivers,disease spread, and industrial waste dumped into rivers
Effect: fish die off, destroyed habitats, oil spills on land that mixes with run off
Please give brainliest if i helped and good luck!
Explanation:
Given that,
Distance 1, r = 100 m
Intensity, ![I_1=1.24\times 10^{-8}\ W/m^2](https://tex.z-dn.net/?f=I_1%3D1.24%5Ctimes%2010%5E%7B-8%7D%5C%20W%2Fm%5E2)
If distance 2, r' = 25 m
We need to find the intensity and the intensity level at 25 meters. Intensity and a distance r is given by :
.........(1)
Let I' is the intensity at r'. So,
............(2)
From equation (1) and (2) :
![I'=\dfrac{Ir}{r'^2}](https://tex.z-dn.net/?f=I%27%3D%5Cdfrac%7BIr%7D%7Br%27%5E2%7D)
![I'=\dfrac{1.24\times 10^{-8}\times 100}{25^2}](https://tex.z-dn.net/?f=I%27%3D%5Cdfrac%7B1.24%5Ctimes%2010%5E%7B-8%7D%5Ctimes%20100%7D%7B25%5E2%7D)
![I'=1.98\times 10^{-9}\ W/m^2](https://tex.z-dn.net/?f=I%27%3D1.98%5Ctimes%2010%5E%7B-9%7D%5C%20W%2Fm%5E2)
Intensity level is given by :
, ![I_o=10^{-12}\ W/m^2](https://tex.z-dn.net/?f=I_o%3D10%5E%7B-12%7D%5C%20W%2Fm%5E2)
![dB=10\ log(\dfrac{1.98\times 10^{-9}}{10^{-12}})](https://tex.z-dn.net/?f=dB%3D10%5C%20log%28%5Cdfrac%7B1.98%5Ctimes%2010%5E%7B-9%7D%7D%7B10%5E%7B-12%7D%7D%29)
dB = 32.96 dB
Hence, this is the required solution.
Answer:
the heat absorbed by the block of copper is 74368.476J
Explanation:
Hello!
To solve this problem use the first law of thermodynamics that states that the heat applied to a system is the difference between the initial and final energy considering that the mass and the specific heat do not change so we can infer the following equation
Q=mCp(T2-T1)
Where
Q=heat
m=mass=2.3kg
Cp=0.092 kcal/(kg C)=384.93J/kgK
T2=Final temperatura= 90C
T1= initial temperature=6 C
solving
![Q=(2.3kg)(384.93\frac{J}{kgC} )(90C-6C)=74368.476J](https://tex.z-dn.net/?f=Q%3D%282.3kg%29%28384.93%5Cfrac%7BJ%7D%7BkgC%7D%20%29%2890C-6C%29%3D74368.476J)
the heat absorbed by the block of copper is 74368.476J
We can rearrange the mirror equation before plugging our values in.
1/p = 1/f - 1/q.
1/p = 1/10cm - 1/40cm
1/p = 4/40cm - 1/40cm = 3/40cm
40cm=3p <-- cross multiplication
13.33cm = p
Now that we have the value of p, we can plug it into the magnification equation.
M=-16/13.33=1.2
1.2=h'/8cm
9.6=h'
So the height of the image produced by the mirror is 9.6cm.
Answer:
Explanation:
The combined wave only end up been more powerful than the Longitudinal wave. This means, the transverse wave is more powerful than the combined wave. In transverse wave, the oscillation is perpendicular to the direction of the wave, while in longitudinal wave, the motion of the movement of the object is parallel to the movement of the wave. And in combined wave, the movement of the medium is in a circular manner,