Dry air will break down if the electric field exceeds 3.0*10^6 V/m. What amount of charge can be placed on a parallel-plate capacitor if the area of each plate is 73 cm^2?

Respuesta :

Answer:

The charge on each plate of the capacitor is [tex]19.38 \mu C[/tex]

with one plate positive and one negative, i.e., [tex]\pm 19.38 \mu C[/tex]

Solution:

According to the question:

Critical value of Electric field, [tex]E_{c} = 3.0\times 10^{6} V/m[/tex]

Area of each plate of capacitor, [tex]A_{p} =73 cm^{2} = 73\times 10^{- 4} m^{2}[/tex]

Now, the amount of charge on the capacitor's plates can be calculated as:

Capacitance, C  = [tex]\frac{epsilon_{o}\times Area}{Distance, D}[/tex]        (1)

Also, Capacitance, C = [tex]\frac{charge, q}{Voltage, V}[/tex]

And

Electric field, E = [tex]\frac{Voltage, V}{D}[/tex]

So, from the above relations, we can write the eqn for charge, q as:

q = [tex]\epsilon_{o}\times E_{c}\times A_{p}[/tex]

q = [tex]8.85\times 10^{- 12}\times 3.0\times 10^{6}\times 73\times 10^{- 4}[/tex]

[tex]q = 19.38 \mu C[/tex]