Properly input current above 40 voltage or 100 for example elecrical fan machine is used to perform a task, work output is always more than work
Answer:
U= 1.9*10^-7
Explanation:
given:
<em>L=8 cm</em>
<em>d_1=d_2=2.05_10^-3</em>
<em>K_py=4.3</em>
<em>K_po=3</em>
<em>V_ab=86 V</em>
required
U=??
solution:
the energy stored in the capacitor
U=1/2C_t*V^2_ab (1)
voltage is known but capacitance is not
we can consider the two plates of polystyrene and pyrex glass as a two separate capacitors connected on series so the total capacitance of series capacitor is given by:
1/C_t= 1/C_py+1/C_po (2)
the capacitance of polystyrene
C_po=K_po*A/d
=8.9*10^-11
= 89 pF
the capacitance of pyrex
C_py=K_py*A/d
=128 pF
substitution in 2 yields
1/C_t= 1/128+1/89
C_t= 52.6 pF
substitution in 1 yields
U=1/2C_t*V^2_ab
= 1.9*10^-7
<span>1 C = 6.24150965(16)×10^18 electrons
31.25 x 10^18 electrons / (6.24150965(16)×10^18 electrons / C) = 5.007 Coulombs
</span><span>I hope this helps. </span>
