1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Wewaii [24]
3 years ago
9

A river with a flow rate of 7 m3/s discharges into a lake with a volume of 9,000,000 m3. The concentration of a particular VOC i

n the river is 3 mg/L. The lake has a decay coefficient for the VOC of 0.3 per day. What is the concentration of the VOC in the river downstream?
Physics
1 answer:
soldi70 [24.7K]3 years ago
4 0

Answer:

The concentration downstream reduces to 0.03463mg/L

Explanation:

Initially let us calculate the time it is required to fill the lake, since for that period of time the pollutant shall remain in the lake before being flushed out.

Thus the detention period is calculated as

t=\frac{V}{Q}\\\\t=\frac{9000000}{7}=1.285\times 10^{6}seconds\\\\\therefore t = 14.872days

Now the concentration of the pollutant after 14.872 days is calculated as

N_{t}=N_{0}e^{-kt}

where

N_{o} is the initial concentration

't' is the time elapsed after which the remaining concentration is calculated

k is the dissociation constant.

Applying values we get

N_{t}=3\times e^{-0.3\times 14.872}

N_{t}=0.03463mg/L

You might be interested in
How is shooting a shotgun related to newtons third law ? why does a rifle have less “kick” then a shotgun ?
Mazyrski [523]
Newton’s third law is a force is a push or pull that acts upon an object as a result of another object.. A shot gun when fired pulls back when a force (you pulling the trigger) is acted upon it. This is how it relates. A rifle has less kick than a shot gun because the rifle is smaller and has less of a force than a shot gun.
5 0
3 years ago
I need this ASAP please!!!
WINSTONCH [101]
It’s E we just had a test in this and I got it right
4 0
2 years ago
Read 2 more answers
Are the days with the longest daylight always in the summer? Are the days with the shortest daylight always in the winter? Expla
jok3333 [9.3K]
The day with the longest daylight is the beginning of Summer.
After that, they start to get shorter.

The day with the shortest daylight is the beginning of Winter.
After that, they start to get longer.
6 0
4 years ago
Please help!! giving a lot of points
Readme [11.4K]

Question 1.

  • mass = 4500 kg
  • potential energy (p.e) = 67500 J

now, we know :

=》

p.e =  mgh

=》

67500 = 4500 \times 10 \times h

=》

67500 = 45000 \times h

=》

h =  \dfrac{67500}{45000}

=》

h = 1.5 \: m

note : if we take acceleration due to gravity as 9.8, then height = 1.53 m

Question 2.

  • mass = 4500 kg
  • kinetic energy = 63000 j

we know,

=》

k.e =  \dfrac{1}{2} mv {}^{2}

=》

63000 =  \dfrac{1}{2}  \times 4500 \times  {v}^{2}

=》

{v}^{2}  =  \dfrac{63000 \times 2}{4500}

=》

{v}^{2}  = 28

=》

v =  \sqrt{28}

=》

v = 2 \sqrt{7} \:  \:  ms {}^{ - 1}

or

=》

5.29 \:  \: ms {}^{ - 1}

7 0
3 years ago
One has a frequency of 490 Hz and the other is 488 Hz. How many beats per second are heard?
tresset_1 [31]
When sounds at two different frequencies are combined,
two new sounds are created ... at the sum and difference
of the original frequencies.

Combining two sounds at 490 Hz and 488 Hz creates
beats at  978 Hz and 2 Hz.

The fluttering "wah wah" effect of the 2 Hz beat is much more
noticeable than the new sound at 978 Hz.
7 0
3 years ago
Other questions:
  • A space heater primarily converts electrical energy into
    9·1 answer
  • What is the frequency of a wave if 3 crests pass in 6 seconds?
    15·2 answers
  • The coloring of the blue morpho butterfly is protective. As the butterfly flaps its wings, the angle at which light strikes the
    11·1 answer
  • Which statement is true about a farsighted (hyperopic) eye?
    12·1 answer
  • You throw a bowling ball down an alley with speed v_0v ​0 ​​ , and initially it slides without rolling. After a little while fri
    11·1 answer
  • When you throw a pebble straight up with initial speed V, it reaches a maximum height H with no air resistance. At what speed sh
    7·1 answer
  • Mass is the amount of what​
    5·1 answer
  • 13. Under what condition (if any) does a moving body experience no energy even though there
    9·1 answer
  • What is an example of a system and describe the energy flow through it.
    9·1 answer
  • How to reduce fluid friction
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!