This problem explores what happens to the resting steady state of a membrane, after the ion pumps are suddenly turned off, say by addition of a neurotoxin. namely, sodium ions are far from equilibrium in the resting state. the concentration of sodium inside the cell is 12mm, while outside the cell it is 145mm; the membrane voltage is vmem = -90 mv. this means that when pumps are turned off, sodium will rush into the cell
find the charge per unit length of the axon contributed by all the sodium ions inside the axon (5 points). what would the corresponding quantity equal if the interior concentration of sodium matched the fixed exterior concentration

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

conduction is the transfer of thermal energy (heat in transfer) due to collisions between the molecules in the object. collisions between adjacent atoms and molecules transfer kinetic energy from the warmer to the cooler object. the objects must be in physical contact.

the dissolution of polymer can be thermodynamically described in 2 steps.