A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid bya membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness isestimated to be 98 nm and has a dielectric constant of 5.00.(a) If an average red blood cell has a mass of 1.10 × 10¬12kg, estimate the volume of the cell and thus find its surface area. The density of blood is 1,100 kg/m³. (Assumethe volume of blood due to components other than red blood cells is negligible.)volume1E-15m3surface area4.8E-10m2(b) Estimate the capacitance of the cell by assuming the membrane surfaces act as parallel plates.2.2E-13(c) Calculate the charge on the surface of the membrane.2.2E-14How many electronic charges does the surface charge represent?1.4E5Your response is within 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all intermediate results to atleast four-digit accuracy to minimize roundoff error.

thickness of membrane = 98 nm dielectric constant = 5 mass of average red blood cell = 1.10×10-12 kg…

A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid by a membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness is estimated to be 98 nm and has a dielectric constant of 5.00. (a) If an average red blood cell has a mass of 1.10 x 10-12 kg, estimate the volume of the cell and thus find its surface area. The density of blood is 1,100 kg/m3. (Assume the volume of blood due to components other than red blood cells is negligible.) v m3 volume 1E-15 surface area 4.8E-10 v m2 (b) Estimate the capacitance of the cell by assuming the membrane surfaces act as parallel plates. 2.2E-13 (c) Calculate the charge on the surface of the membrane. 2.2E-14 C How many electronic charges does the surface charge represent? 1.4E5

A model of a red blood cell portrays the cell as a spherical capacitor, a positively charged liquid sphere of surface area A separated from the surrounding negatively charged fluid by a membrane of thickness t. Tiny electrodes introduced into the interior of the cell show a potential difference of 100 mV across the membrane. The membrane's thickness is estimated to be 98 nm and has a dielectric constant of 5.00. (a) If an average red blood cell has a mass of 1.10 x 10-12 kg, estimate the volume of the cell and thus find its surface area. The density of blood is 1,100 kg/m3. (Assume the volume of blood due to components other than red blood cells is negligible.) v m3 volume 1E-15 surface area 4.8E-10 v m2 (b) Estimate the capacitance of the cell by assuming the membrane surfaces act as parallel plates. 2.2E-13 (c) Calculate the charge on the surface of the membrane. 2.2E-14 C How many electronic charges does the surface charge represent? 1.4E5

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter20: Electric Potential And Capacitance

Section: Chapter Questions

Problem 71P

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