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
zysi [14]
3 years ago
11

To aid in the prevention of tooth decay, it is recommended that drinking water contain 0.800 ppm fluoride, F−. How many grams of

F− must be added to a cylindrical water reservoir having a diameter of 2.02 × 102 m and a depth of 87.32 m?
Physics
1 answer:
Leviafan [203]3 years ago
4 0

Answer:

2.23 × 10^6 g of F- must be added to the cylindrical reservoir in order to obtain a drinking water with a concentration of 0.8ppm of F-

Explanation:

Here are the steps of how to arrive at the answer:

The volume of a cylinder = ((pi)D²/4) × H

Where D = diameter of the cylindrical reservoir = 2.02 × 10^2m

H = Height of the reservoir = 87.32m

Therefore volume of cylindrical reservoir = (3.142×202²/4)m² × 87.32m = 2798740.647m³

1ppm = 1g/m³

0.8ppm = 0.8 × 1g/m³

= 0.8g/m³

Therefore to obtain drinking water of concentration 0.8g/m³ in a reservoir of volume 2798740.647m³, F- of mass = 0.8g/m³ × 2798740.647m³ = 2.23 × 10^6 g must be added to the tank.

Thank you for reading.

You might be interested in
Determine the ratio of the flow rate through capillary tubes A and B (that is, Qa/Qb).
Oliga [24]

To solve this problem we can use the concepts related to the change of flow of a fluid within a tube, which is without a rubuleous movement and therefore has a laminar fluid.

It is sometimes called Poiseuille’s law for laminar flow, or simply Poiseuille’s law.

The mathematical equation that expresses this concept is

\dot{Q} = \frac{\pi r^4 (P_2-P_1)}{8\eta L}

Where

P = Pressure at each point

r = Radius

\eta = Viscosity

l = Length

Of all these variables we have so much that the change in pressure and viscosity remains constant so the ratio between the two flows would be

\frac{\dot{Q_A}}{\dot{Q_B}} = \frac{r_A^4}{r_B^4}\frac{L_B}{L_A}

From the problem two terms are given

R_A = \frac{R_B}{2}

L_A = 2L_B

Replacing we have to

\frac{\dot{Q_A}}{\dot{Q_B}} = \frac{r_A^4}{r_B^4}\frac{L_B}{L_A}

\frac{\dot{Q_A}}{\dot{Q_B}} = \frac{r_B^4}{16*r_B^4}\frac{L_B}{2*L_B}

\frac{\dot{Q_A}}{\dot{Q_B}} = \frac{1}{32}

Therefore the ratio of the flow rate through capillary tubes A and B is 1/32

6 0
3 years ago
I desperately need help with my Physics Exam I am failing this class will mark Brainliest to whoever helps the most: PART 1 (I d
GREYUIT [131]
  1. Option 2nd is correct

  1. last option is correct
6 0
2 years ago
The density of aluminum is 2.7 g/cm3. A metal sample has a mass of 52.0 grams and a volume of 17.1 cubic centimeters. Could the
Fudgin [204]
 Answer:  
__________________________________________________
            No;  the sample could not be aluminum;
since the density of aluminum, " 2.7 g/cm³ " , is NOT close enough to the density of the sample, " 3.04 g/cm³ " .
________________________________________________
Explanation:
________________________________________________
Density is expressed as "mass per unit volume" ;

  in which:
     "mass, "m", is expressed in units of "g" (grams);  and:
     "Volume, "V", is expressed in units of "cm³ " (such as in this problem); or                                                   in units of "mL" ;
__________________________________________________
            {Note the exact conversion:  " 1 cm³ = 1 mL " .}. 
__________________________________________________
  The formula for density:  D = m/V ;

Given:  The density of aluminum is:  2.7 g/cm³.

Given:  A sample has a mass of 52.0 g ; and Volume of 17.1 cm³ ; could it be aluminum?
_________________________________________________________
Let us divide the mass of the sample by the volume of the sample;
by using the formula:
___________________________________________
            D = m / V ;  

     and see if the value is at, or very close to "2.7 g/cm³ ".  

If it is, then it could be aluminum.
____________________________________________________
The density for the sample:

  D = (52.0 / 17.1)   g/cm³ = 3.0409356725146199 g/cm³ ;
                                              →round to "3 significant figures" ;
                                          = 3.04 g/cm³ .
_______________________________________________
No; the sample could not be aluminum; since the density of aluminum, 
   "2.7 g/cm³ "   is NOT close enough to the density of the sample,
                        "3.04 g/cm³ " .
____________________________________________________
5 0
3 years ago
Which in is it Speed (S) or Velocity (V)?
Andrej [43]

Explanation:

Speed has only magnitude.

Velocity has magnitude and direction.

"A bike goes 25 m/s toward  main street."

This includes a direction, so it is velocity (V).

"A person walks 4 mph."

This has only magnitude, so it is speed (S).

"A plane flies 200 m/s."

This has only magnitude, so it is speed (S).

"A bird flies 100 mph due south."

This includes a direction, so it is velocity (V).

8 0
3 years ago
How are cactus adapted to survive in deserts?
andreev551 [17]

1. They have evolved their leaves into spikes for minimum water loss through transpiration.

2. They have a waxy layer for minimum water loss.

3. They have thick walls for minimum water loss.

4. They can take water from atmosphere.

5. They change the photo energy from Sun into an intermediate stage and store it, so that they can make food even in night.

7 0
2 years ago
Other questions:
  • Design a rectangular milk carton box of width ww, length ll, and height hh which holds 474 cm3474 cm3 of milk. The sides of the
    13·1 answer
  • We can block light by placing obstacles in its path, but it’s much more difficult to block sound. Why?
    7·2 answers
  • 1.When I cook an egg in a microwave oven, the device uses electromagnetic energy to increase the kinetic energy of particles of
    9·1 answer
  • 4. Elijah does 44 joules of work against gravity to pull a 0.5-kilogram rope with a 1.0-kilogram bucket attached up to the floor
    14·1 answer
  • PLEASE HELP ASAP!!! CORRECT ANSWERS ONLY PLEASE!!!
    15·2 answers
  • To practice Problem-Solving Strategy 25.1 Resistor Circuits. Find the currents through and the potential difference across each
    11·1 answer
  • Late on an autumn day, the relative humidity is 44.0% and the temperature is 20.0°C. What will the relative humidity be that ev
    6·1 answer
  • What are the three main ideas associated with Newton’s second law of motion? List these in your own words .
    6·1 answer
  • A motorcyclist is making an electric vest that, when connected to the motorcycle's 12 V battery, will warm her on cold rides. Sh
    10·1 answer
  • The yearly whole-body dose caused by radioactive 40K absorbed in our tissues is 17 mrem. Note: 40K also emits gamma rays, many o
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!