Question

In: Physics

1. If you apply the potential difference V to a parallel plate capacitor, it is charged...

1. If you apply the potential difference V to a parallel plate capacitor, it is charged to the charge value Q. Now you double the separation between the plates keeping the same V. As a result, charge on the plates will be equal to:

A. 2Q;

B. 4Q;

C. Q;

D. Q/2;

E. Q/4;

2. You have several capacitors of different capacitances. Which statement is correct?

A. If the capacitors connected to a battery in series, charges on all capacitors are the same, but potential differences are different;

B. If the capacitors connected to a battery in series, charges on all capacitors are different, but potential differences are the same;

C. If the capacitors connected to a battery in parallel, charges on all capacitors are different, but potential differences are the same;

D. If the capacitors connected to a battery in parallel, charges on all capacitors are the same, but potential differences are different;

E. A and C;

F. B and D.

3. If you apply voltage V to a long aluminum wire, the power P is dissipated in the wire. If you apply the same voltage V to another aluminum wire which has the same diameter, but is 2 times longer, the dissipated power will be equal to:

A. 4P;

B. 2P;

C. P;

D. P/2;

E. P/4.

Expert Solution

1. Correct Answer: D. Q/2, Capacitance is inversely proportional to the separation between the plates. If you double the separation between the plates the capacitance becomes half. Further, as the voltage is constant the charge on the plates is proportional to the capacitance. Hence charge becomes half.

2. Correct Answer: E. A and C, In the series connection of different capacitors, charge on each capacitor is the same. Voltage on each capacitor is inversely proportional to the capacitance. In a parallel connection of different capacities, voltage is the same because along parallel parts voltage is always the same. Further, charge on each capacitor is proportional to the capacitance.

3. Correct Answer:D. P/2 , For a given voltage, power consumed is inversely proportional to the resistance of the wire. If the length of the wire becomes double, its resistance also doubles. Hence the power consumed will become half.

genius_generous answered 2 years ago

When a potential difference of 142 V is applied to the plates of a parallel-plate capacitor,...

When a potential difference of 142 V is applied to the plates of a parallel-plate capacitor, the plates carry a surface charge density of 45.0 nC/cm2. What is the spacing between the plates?

Electric Potential (Parallel Plate Capacitor Potential Energy and Potential) A parallel plate capacitor has two terminals,...

Electric Potential (Parallel Plate Capacitor Potential Energy and Potential) A parallel plate capacitor has two terminals, one (+) and the other (-). When you move a test positive charge, q at uniform velocity from the negative terminal (Ui and Vi) to the positive terminal (Uf and Vf), work W = ΔU = qΔV is done on the charge, increasing the energy of the field by this amount. The work done by the field on the charge is – W. (V...

Two identical parallel-plate capacitors, each with capacitance 20.0 μF, are charged to potential difference 40.0 V...

Two identical parallel-plate capacitors, each with capacitance 20.0 μF, are charged to potential difference 40.0 V and then disconnected from the battery. They are then connected to each other in parallel with plates of like sign connected. Finally, the plate separation in one of the capacitors is doubled. (a) Find the total energy of the system of two capacitors before the plate separation is doubled. (b) Find the potential difference across each capacitor after the plate separation is doubled. (c)...

The potential difference across a charged capacitor is 22 V. The capacitor discharges through a fixed...

The potential difference across a charged capacitor is 22 V. The capacitor discharges through a fixed resistor. After a time equal to the time constant, the potential difference has reduced to V. The magnitude of V is:

A 4.0-cm-diameter parallel-plate capacitor with a 1.0 mm spacing is charged to 1000 V. A switch...

A 4.0-cm-diameter parallel-plate capacitor with a 1.0 mm spacing is charged to 1000 V. A switch closes at t =0s, and the capacitor is discharged through a wire with 0.20? resistance. Part A Find an expression for the magnetic field strength inside the capacitor at r =1.0cm as a function of time t (where t is in ps). Part B Draw a graph of B versus t.

a parallel-plate capacitor is oriented horizontally and charged so that there is an electric field of...

a parallel-plate capacitor is oriented horizontally and charged so that there is an electric field of 50,000 V/m pointing up inside the gap of 1cm, which is filled with air. a.) With the charge on each plate remaining constant, the capacitor is immersed half-way in an oil of dielectric constant K=2.5 What is now the potential difference between the plates? b.) If on top of the oil, water (K=80) is poured to completely fill the upper part of the gap,...

A parallel-plate air capacitor of area A=12.0cm2 and plate separation d=3.80mm is charged by a battery...

A parallel-plate air capacitor of area A=12.0cm2 and plate separation d=3.80mm is charged by a battery to a voltage 66.0V. If a dielectric material with kappa=3.60 is inserted so that it fills the volume between the plates (with the capacitor still connected to the battery), how much additional charge will flow from the battery onto the positive plate?

A parallel plate capacitor consisting of square plates is charged. One edge of the plates is...

A parallel plate capacitor consisting of square plates is charged. One edge of the plates is 0.4 (m). When the current is 5 (A), the rate of change of the electric field between the plates is approximately how many V / (m.s). Eo = 8.85x10-12 (SI)

You have a parallel-plate 6.33 × 10-6 F capacitor that is charged to 0.00861 C. While...

You have a parallel-plate 6.33 × 10-6 F capacitor that is charged to 0.00861 C. While the capacitor is isolated, you change the plate separation so that the capacitance becomes 2.41 × 10-6 F. How much work do you perform in this process?

A parallel plate capacitor with plate separation d is connected to a battery. The capacitor is...

A parallel plate capacitor with plate separation d is connected to a battery. The capacitor is fully charged to Q Coulombs and a voltage of V. (C is the capacitance and U is the stored energy.) Answer the following questions regarding the capacitor charged by a battery. For each statement below, select True or False. With the capacitor connected to the battery, decreasing d increases U. A: True B: False After being disconnected from the battery, inserting a dielectric with...