A tiny bacterium with a mass of 10-14 kg is confined between two rigid walls 0.1 mm apart. Its minimum speed is:______a. 3.3 x 10^-14 m/s b. 3.3 × 10^-16m/s c. 2.6× 10^-14 m/s d. 1.3×10^-14 m/s e. 1.3 x 10^-16 m/s

Respuesta :

Answer:

b. [tex]3.313\times 10^{-16}\ m/s[/tex]

Explanation:

h = Planck's constant = [tex]6.626\times 10^{-34}\ m^2kg/s[/tex]

m = Mass of bacterium = [tex]10^{-14}\ kg[/tex]

L = Gap = 0.1 mm

Energy of a particle moving in a one dimensional box is given by

[tex]E=\dfrac{n^2h^2}{8mL^2}\\\Rightarrow E=\dfrac{1^2\times (6.626\times 10^{-34})^2}{8\times 10^{-14}\times (0.1\times 10^{-3})^2}\\\Rightarrow E=5.48798\times 10^{-46}\ J[/tex]

Kinetic energy is given by

[tex]K=\dfrac{1}{2}mv^2\\\Rightarrow E=\dfrac{1}{2}mv^2\\\Rightarrow v=\sqrt{\dfrac{2E}{m}}\\\Rightarrow v=\sqrt{\dfrac{2\times 5.48798\times 10^{-46}}{10^{-14}}}\\\Rightarrow v=3.313\times 10^{-16}\ m/s[/tex]

The minumum speed is [tex]3.313\times 10^{-16}\ m/s[/tex]