Which action is due to field forces?

The membrane that surrounds a certain type of living cell has a surface area of 7.1 x 10-9 m2 and a thickness of 1.5 x 10-8 m. A

hoa [83]

Answer:

Q = +1.4 pC

Explanation:

The capacitance of any capacitor, by definition, is as follows:
$C = \frac{Q}{V} (1)$
Applying Gauss'Law and the definition of electric potential, it can be showed that the capacitance of a parallel-plate capacitor can be expressed as follows:
$C = \frac{\epsilon_{r}*\epsilon_{0} * A}{d} (2)$
Where εr is the dielectric constant of the material that fills the space between the plates, A is the area of one of the plates, and d, is the separation between them.
Replacing by the givens in (2) we can find the value of the capacitance C, as follows:

$C = \frac{\ 4.4*8.85e-12C2/N*m2*7.1e-9m2}{1.5e-8m} = 18.4e-12 F = 18.4 pF$

Replacing the values of C and V in (1), we can solve for Q, as follows:

$Q = C*V = 18.4e-12 F* 75.9e-3 V = 1.4e-12 C = +1.4 pC$

As the outer surface is at a higher potential that the inside surface, the charge on it must be positive, and is equal to +1.4 pC.

7 0

3 years ago

Waves A and B have the same speed, but wave A has a shorter wavelength. Which wave has the higher frequency?

Nuetrik [128]

Frequency and wavelength are inversely proportional.
A shorter wavelength implies a higher frequency.

3 0

3 years ago

The closure temperature represents the point when ________. A. a magma cools to the point where minerals begin to crystallize B.

melomori [17]

The closure temperature represents the point when isotopes are no longer free to move out of a crystal lattice.

Answer: Option C

<u>Explanation:</u>

The closure temperature can also be termed as blocking temperature. It is mostly used in radiometric dating. As the temperature decreases, below a certain point the isotopes may get freeze in their lattice positions. And there may be slowing of diffusion.

At the closure temperature, that rate of diffusion will be zero as the isotopes will be no longer free to move out of crystal lattice. So, this is termed as closure or blocking temperature. As the isotopes loose their ability to move, their concentration will remain fixed in their position leading to measurement of radiation dating.

5 0

3 years ago

What is the average speed of a car that traveled 300.0 miles in 5.5 hours?

Pavlova-9 [17]

<span>i think the average speed was 54.54 (mph)</span>

7 0

3 years ago

Read 2 more answers

A ball is thrown upward with an initial vertical velocity of v0 to a maximum height of hmax and falls back toward earth. on the

Vlad1618 [11]

Answer: $v_f=g\frac{t}{2}$

The ball was thrown at the speed of $v_o$ .

Maximum height achieved is $h_{max}$

Time of flight is t.

Now, the time the ball takes to achieve maximum height = the time taken by ball to fall back = $\frac{t}{2}$

let us just consider the second half of the flight. At $h_{max}$ , the velocity would be zero. let us consider as the initial velocity for the second half of the flight i.e. $v_i=0$

Using the equation of motion:

$v_f=v_i+at$

where, $v_f$ is the final velocity, a is the acceleration, t is the time taken.

Because the ball would fall under gravity, hence a=g and time of flight would be t/2

$\Rightarrow v_f=0+g\frac {t}{2}$

5 0

3 years ago