Calculate the Number of Influenza Viruses on You

[gmunoz18]

Homework Statement

A typical virus is a packet of protein and DNA (or RNA) and can be spherical in shape. The influenza A virus is a spherical virus that has a diameter of 85 nm. If the volume of saliva coughed onto you by your friend with the flu is 0.023 cm3 and 10^-9 of that volume consists of viral particles, how many influenza viruses have just landed on you?

Homework Equations

v=(4/3)*pi*r^3

The Attempt at a Solution

4/3*pi*42.5^3=volume of virus

321555 nm^3 volume of one virus

(.023cm^3)*(10^-9)= 2.3e-10 cm^3 contains virus = .0023 nl


Which part of my math is wrong? this just doesn't seem right at all. The volume of one virus is less than what spilled on him.

 

[nicksauce]

I would convert .023cm^3 into nm^3, then find out how many total virus particles there are, then multiply by 10^-9.

 

[granpa]

how many nanometers are in a centimeter?

 

[gmunoz18]

how many nanometers are in a centimeter?

10 million

 

[granpa]

how many cubic nanometers in a cubic centimeter?

 

[gmunoz18]

how many cubic nanometers in a cubic centimeter?

1e21

 

[granpa]

how many nanometers of spit?

 

[HallsofIvy]

Homework Statement

A typical virus is a packet of protein and DNA (or RNA) and can be spherical in shape. The influenza A virus is a spherical virus that has a diameter of 85 nm. If the volume of saliva coughed onto you by your friend with the flu is 0.023 cm3 and 10^-9 of that volume consists of viral particles, how many influenza viruses have just landed on you?

Homework Equations

v=(4/3)*pi*r^3

The Attempt at a Solution

4/3*pi*42.5^3=volume of virus

321555 nm^3 volume of one virus

(.023cm^3)*(10^-9)= 2.3e-10 cm^3 contains virus = .0023 nl

.023= 2.3*10^-2. (.023)(10^-9)= 2.3*10^-11.

Which part of my math is wrong? this just doesn't seem right at all. The volume of one virus is less than what spilled on him.

You have calculated The volume of one virus and the volume of all the viruses. Convert to the same units and divide the volume of all the viruses by the volume of one to determine how many viruses there were.

 

[gmunoz18]

how many nanometers of spit?

2.3e19

 

[granpa]

how many nanometers of virus?

 

[gmunoz18]

how many nanometers of virus?

2.3e11

so at this point could I just do 2.3e11/321555?

and come up with 715274

 

[granpa]

10^-9=1e-9

yes, you simply divide

 

[gmunoz18]

thanks a lot for the walkthrough help!