1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
likoan [24]
3 years ago
6

The membrane that surrounds a certain type of living cell has a surface area of 5.1 x 10-9 m2 and a thickness of 1.4 x 10-8 m.

Physics
1 answer:
ziro4ka [17]3 years ago
6 0

a) The charge on the outer surface is 1.2\cdot 10^{-12} C

b) The number of ions is 7.5\cdot 10^6

Explanation:

a)

The membrane behaves as a parallel plate capacitor, whose capacity is given by the equation

C=\frac{k\epsilon_0 A}{d}

where

k = 4.3 is the dielectric constant

\epsilon_0 =8.85\cdot 10^{-12} F/m is the vacuum permittivity

A=5.1\cdot 10^{-9} m^2 is the surface area

d=1.4\cdot 10^{-8} m is the distance between the two plates

Substituting,

C=\frac{(4.3)(8.85\cdot 10^{-12})(5.1\cdot 10^{-9})}{1.4\cdot 10^{-8}}=1.4\cdot 10^{-11} F

The capacity of the membrane is related to the potential difference between the two surfaces by

C=\frac{Q}{\Delta V}

where here we have

Q = excess charge on one surface

\Delta V = 85.5 mV = 0.0855 V is the potential difference between the two surfaces

Solving for Q, we find

Q=C\Delta V=(1.4\cdot 10^{-11})(0.0855)=1.2\cdot 10^{-12} C

b)

We said that the net charge on the outer surface is

Q=1.2\cdot 10^{-12} C

The charge of one K+ ions is equal to the electron charge

+e=1.6\cdot 10^{-19} C

Therefore, the number of ions on the outer surface can be found by dividing the total charge by the charge of a single ion:

N=\frac{Q}{e}=\frac{1.2\cdot 10^{-12}}{1.6\cdot 10^{-19}}=7.5\cdot 10^6

Learn more about capacity:

brainly.com/question/10427437

brainly.com/question/8892837

brainly.com/question/9617400

#LearnwithBrainly

You might be interested in
In covalent bonds what is being shared
gulaghasi [49]

Answer:

Image result for In covalent bonds what is being shared

A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are known as shared pairs or bonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding.

Explanation:

8 0
2 years ago
The doppler effect is when objects are not moving?<br><br> True <br><br> False
SVETLANKA909090 [29]

Answer:

reviewing the statement we can say that it is FALSE

Explanation:

The Doppler effect is the change in the perceived frequency of a sound wave by the RELATIVE MOTION of the source and the observer.

This effect is very useful for finding the speed of an object.

When reviewing the statement we can say that it is FALSE

6 0
2 years ago
Increasing cardiorespiratory fitness levels is difficult for experienced athletes because __________.
Olin [163]
The answer is
C. They have all ready achieved high levels of cardio respiratory fitness.
6 0
3 years ago
A block of stone measures 15cm x 15cm x 20 cm.What is the total surface area of the stone
Sidana [21]

This should help look at the pictures?

7 0
3 years ago
What is cosmic ray spallation
love history [14]

The Cosmic Ray is a natural way for nuclear fission and nucleosynthesis to occur. It refers to the formation of chemical elements from the impact of cosmic rays on an object.

6 0
3 years ago
Read 2 more answers
Other questions:
  • A satellite circles the moon at a distance above its surface equal to 2 times the radius of the moon. The acceleration due to gr
    5·2 answers
  • What are dreams, where do they originate from, why do we have dreams, and are they psychic visions or something? Please explain
    9·1 answer
  • A rock with a mass of 25 kg has a weight of 40.8 n on the moon. what is the value of the acceleration of gravity (g) on the moon
    14·1 answer
  • In the reaction C6H12 + ________ O2----&gt; 6H20 + 6CO2, what coefficient should be placed in front of 02 to balance the reactio
    15·2 answers
  • Who created a steel plow
    12·2 answers
  • How many 3.2cm paperclips could fit on a football field
    10·1 answer
  • Which of the following are not likely to form bonds?
    8·2 answers
  • Need on all if you can.
    14·1 answer
  • Show by dimension that the equation of motion is correct <br>V² = U²+2as​
    8·1 answer
  • Can work output exceed work input?<br> Yes<br> No
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!