1. A capacitor of capacitance \[6\mu F\] is charged upto 100 volt.
The energy stored in the capacitor is
a) 0.6 Joule
b) 0.06 Joule
c) 0.03 Joule
d) 0.3 Joule
Explanation:
2. A parallel plate air capacitor is charged and then isolated.
When a dielectric material is inserted between the plates of
the capacitor, then which of the following does not change
a) Electric field between the plates
b)Potential difference across the plates
c) Charge on the plates
d) Energy stored in the capacitor
Explanation: Because there is no source of charge.
3.Capacitance of a parallel plate capacitor becomes 4/3 times
its original value if a dielectric slab of thickness t = d/2 is
inserted between the plates (d is the separation between
the plates). The dielectric constant of the slab is
a) 8
b) 4
c) 6
d) 2
Explanation:
4. A 10 micro-farad capacitor is charged to 500 V and then its
plates are joined together through a resistance of 10 ohm.
The heat produced in the resistance is
a) 500 J
b) 250 J
c) 125 J
d) 1.25 J
Explanation:
5. The unit of electric permittivity is
a) \[Volt/m^{2}\]
b) Joule/coulomb
c) Farad/m
d) Henry/m
Explanation:
6.The work done in placing a charge of \[8\times 10^{-18}\] coulomb on
a condenser of capacity 100 micro-farad is
a) \[32\times 10^{-32}Joule\]
b) \[16\times 10^{-32}Joule\]
c) \[3.1\times 10^{-26}Joule\]
d) \[4\times 10^{-10}Joule\]
Explanation:
7. 64 drops of mercury each charged to a potential of 10 V .
They are combined to form one bigger drop. The potential
of this drop will be (Assume all the drops to be spherical)
a) 160 V
b) 80 V
c) 10 V
d) 640 V
Explanation:
8. A spherical drop of mercury having a potential of 2.5 V is
obtained as a result of merging 125 droplets. The potential
of constituent droplets would be
a) 1.0 V
b) 0.5 V
c) 0.2 V
d) 0.1 V
Explanation:
9.A parallel plate capacitor of capacity \[C_{0}\] is charged to a
potential \[V_{0}\]
(i) The energy stored in the capacitor when the battery is
disconnected and the separation is doubled \[E_{1}\]
(ii) The energy stored in the capacitor when the charging
battery is kept connected and the separation between
the capacitor plates is doubled is \[E_{2}\] . Then \[E_{1}/E_{2}\]
value is
a) 4
b) 3/2
c) 2
d) 1/2
Explanation:
10. A parallel plate capacitor carries a charge q . The distance
between the plates is doubled by application of a force. The
work done by the force is
a) Zero
b) \[\frac{q^{2}}{C}\]
c) \[\frac{q^{2}}{2C}\]
d) \[\frac{q^{2}}{4C}\]
Explanation:
