(Capacitance and capacitors) Additional Questions (Capacitance and capacitors) General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan Two capacitors, C1=2mF and C2=16mF, are connected in parallel.  What is the value of the equivalent capacitance of the combination? (2) Calculate the equivalent capacitance of the two capacitors in the previous exercise if they are connected in series. (3) A 100pF capacitor is charged to a potential difference of 50V, the charging battery then being disconnected.  The capacitor is then connected in parallel with a second (initially uncharged) capacitor.  If the measured potential difference drops to 35V, what is the capacitance of this second capacitor? (4) A parallel-plate capacitor has circular plates of 8.0cm radius and 1.0mm separation.  What charge will appear on the plates if a potential difference of 100V is applied? General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan (5) In figure the battery supplies 12V.  (a) Find the charge on each capacitor when switch S1 is closed, and (b) when later switch S2 is also closed.  Assume C1=1mF, C2=2mF, C3=3mF, and C4=4mF. (6) A 16pF parallel-plate capacitor is charged by a 10V battery.  If each plate of the capacitor has an area of 5cm2, 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? (7) The energy density in a parallel plate capacitor is given as 2.1×l0-9.  What is the value of the electric field in the region between the plates? General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan (8) a- Determine the equivalent capacitance for the capacitors shown in figure.   b- If they are connected to 12V battery, calculate the potential difference across each capacitor and the charge on each capacitor                                                                            (9) A 6.0mF capacitor is connected in series with a 4.0mF capacitor and a potential difference of 200 V is applied across the pair. (a) What is the charge on each capacitor? (b) What is the potential difference across each capacitor? (10) Repeat the previous problem for the same two capacitors connected in parallel. General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan [10] In a parallel plate capacitor an electron moves from the positively charged plate to the negatively charged plate. Which of the following are true for the electron? The potential energy increases, and the electrical potential increases. The potential energy increases, and the electrical potential decreases. The potential energy decreases, and the electrical potential increases. The potential energy decreases, and the electrical potential decreases. The potential energy of the electron is unchanged. [11] In Fig. the charge on the 3 micro Farad capacitor is 1 micro Coulomb. What is the voltage across the 2 micro Farad capacitor? General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan [12] A parallel plate capacitor is held at constant voltage. Initially there is only air between the plates. If a dielectric with a dielectric constant of 2 is inserted into the capacitor, what happens to the energy stored in the capacitor? The energy will go up by a factor of 4. The energy will go up by a factor of 2. The energy will be unchanged. The energy will go down by a factor of 2. The energy will go down by a factor of 4. [13] Evaluate the equivalent capacitance of the configuration shown in Figure. All the capacitors are identical, and each has capacitance C. General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan [14] For the system of capacitors shown in Figure, find (a) the equivalent capacitance of the system, (b) the potential across each capacitor, (c) the charge on each capacitor, and (d) the total energy stored by the group [15] Find the equivalent capacitance between points a and b in the combination of capacitors shown in Figure. General Physics 2, Lec 10, By/ T.A. Eleyan

General Physics 2, Lec 10, By/ T.A. Eleyan [15] Two capacitors when connected in parallel give an equivalent capacitance of 9.00 pF and give an equivalent capacitance of 2.00 pF when connected in series. What is the capacitance of each capacitor? [16] Two capacitors when connected in parallel give an equivalent capacitance of Cp and an equivalent capacitance of Cs when connected in series. What is the capacitance of each capacitor? General Physics 2, Lec 10, By/ T.A. Eleyan