Solve Influenza A Virus Problem: 1368350 Viruses

[lalahelp]

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 0.044 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

Volume Influenza A = 4/3(pi)(42.5^3) = 321555 nm
4.4e^11/ 321555= 1368350 viruses landed

What did I do wrong??

 

[Borek]

Why 4.4x10¹¹?

 

[lalahelp]

Isnt that the conversion of .044 Cm^3 to nanometers?

 

[Borek]

That's what you intended it to be, but seems to me like you made an error in calculations.

I can be wrong, it happened before. But show how you got 10¹¹.

 

[lalahelp]

I got it by multiplying .044*10^-9

 

[Clever-Name]

You're trying to change 0.044 cm^3 to nm^3. It's more complicated than just converting 0.044cm to nm

 

[lalahelp]

Dont I have to multiply the -9 by 3 since its cubed
so It will be .044*10^-27

Correct?

 

[Borek]

Dont I have to multiply the -9 by 3 since its cubed
so It will be .044*10^-27

Correct?

Better, but still off. That would work for conversion of cubic meter to cubic nanometers, but you are converting cubic centimeters.

Convert cm³ to m³, then m³ to nm³, that's the safest way (and half of that you already did)

 

[lalahelp]

ok thank you!