الفيزياء العامة الجزء الثاني#موقع الفيزياء.كوم

Lectures in General Physics
2
q
F =
2ε ο
A
6.10) A parallel-plate air capacitor
having area A (40cm 2 ) and spacing
d (1.0 mm) is charged to a potential
V (600V). Find (a) the capacitance,
(b) the magnitude of the charge on
each plate, (c) the stored energy,
(d) the electric field between the
plates and (e) the energy density
between the plates.
6.11) How many 1µF capacitors
would need to be connected in
parallel in order to store a charge
1C with potential of 300V across
the capacitors?
6.12) In figure 6.19 (a)&(b) find the
equivalent capacitance of the
combination. Assume that
C 1 =10µF, C 2 =5µF, and C 3 =4µF.
Calculate the total stored energy in
the system.
6.14) A 16pF parallel-plate capacitor
is charged by a 10V battery. If
each plate of the capacitor has an
area of 5cm 2 , what is the energy
stored in the capacitor? What is the
energy density (energy per unit
volume) in the electric field of the
capacitor if the plates are separated
by air?
6.15) The energy density in a
parallel-plate capacitor is given as
2.1 ×l0 -9 J/m 3 . What is the value of
the electric field in the region
between the plates?
6.16) (a) Determine the equivalent
capacitance for the capacitors
shown in figure 6.20. (b) If they
are connected to 12V battery,
calculate the potential difference
across each capacitor and the
charge on each capacitor
3 F 6 F
Figure 6.19(a)
aa
2
F
Ab
C 1
V
Figure 6.20
Figure6.19(b)
6.13) Two capacitors (2.0µF and
4.0µF) are connected in parallel
across a 300V potential difference.
6.17) Evaluate the effective
capacitance of the configuration
shown in Figure 6.21. Each of the
capacitors is identical and has
capacitance C.
Dr. Hazem Falah Sakeek