446_01c_test2_practice_soln - Test 2 sample problem...

Info icon This preview shows pages 1–2. Sign up to view the full content.

Test # 2 sample problem solutions 1) Considering the expressions relating settling velocity to droplet radius, what is the range in the value of the exponent, a, in w t α r a ? 2 1 3 8 ) 44 . 0 ( 500 Re 3 8 2 24 1 . 0 Re 4 & 3 exp 2 2 2 r w g r w for r w g r r w w for HW in ressions the From t a w t t a w t a t α ρ ρ α ρ ρ ρ η = > = < 2) Approximately what is the ratio of the concentration of cloud condensation nuclei to ice nuclei in a typical volume of air? Although this ratio varies quite a bit, and also depends on the temperature considered, a value of about 10 7 is a reasonable estimate. 3) Will ice crystals grow or shrink if the relative humidity (with respect to liquid water) is 92% and the temperature is –20 o C? growth e e Pa K K Pa T T R L e e e Pa K K Pa T T R L e RH e RH e equation Clapeyron Clausius s K kg J kg J ref w sub s s s K kg J kg J ref w vap s s ref ice ref liquidl > = × = = = = × = = = 3 . 103 253 1 273 1 461 10 83 . 2 exp ) 611 ( 1 1 exp 9 . 116 253 1 273 1 461 10 5 . 2 exp ) 611 )( 92 . 0 ( 1 1 exp : 6 6 4) How can the addition of high concentrations of small hygroscopic aerosols to a warm cloud increase the likelihood of precipitation? The aerosols are too small to form cloud droplets, but they still take up water and grow. By depleting some of the water vapor present in the cloud, these aerosols will decrease the supersaturation. Because of the decreased supersaturation, there will be fewer aerosol particles (already in the cloud) that are capable of activating. In general, the
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 2
This is the end of the preview. Sign up to access the rest of the document.
  • Spring '07
  • Brooks
  • Precipitation, Water vapor, Cloud seeding, Ice nucleus

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern