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It states: The line integral of B.ds around any closed path equals µ0l , where I is the total
continuous current passing through any surface bounded by the closed path.
Kavungya answered the question on May 12, 2021 at 09:07
- Two wires (Fig.4.5), each having a weight per unit length of 1.00 x 10-4 N/m, are parallel with
one directly above the other. Assume that the...(Solved)
Two wires (Fig.4.5), each having a weight per unit length of 1.00 x 10-4 N/m, are parallel with
one directly above the other. Assume that the wires carry currents that are equal in magnitude
and opposite in direction. The wires are 0.10 m apart, and the sum of the magnetic force and
gravitational force on the upper wire is zero. Find the current in the wires. (Neglect Earth’s
magnetic field)
Date posted: May 12, 2021. Answers (1)
- A wire carries a current of 22.0 A from West to East. Assume that at this location the magnetic
field of Earth is horizontal and directed...(Solved)
A wire carries a current of 22.0 A from West to East. Assume that at this location the magnetic
field of Earth is horizontal and directed from south to north and that it has a magnitude of
0.500 x 10-4 T.
(a) Find the magnitude and direction of the magnetic force on a 36.0-m length of wire.
(b) Calculate the gravitational force on the same length of wire if it’s made of copper and has a
cross-sectional area of 2.50 x 10-6 m2.
Date posted: May 12, 2021. Answers (1)
- Figure 4.4 shows an ion of mass m and charge q propelled with a speed v from source S into
a chamber in which a uniform...(Solved)
Figure 4.4 shows an ion of mass m and charge q propelled with a speed v from source S into
a chamber in which a uniform magnetic field B is perpendicular to the path of the ion. The
initially stationary ion from S is accelerated to the chamber by the electric field due to a
potential difference V.
Date posted: May 12, 2021. Answers (1)
- What magnetic field strength is necessary so that an electron moving with a speed of 5 x 105 m/s
travels in a circle of radius 1...(Solved)
What magnetic field strength is necessary so that an electron moving with a speed of 5 x 105 m/s
travels in a circle of radius 1 m?
Date posted: May 12, 2021. Answers (1)
- A proton moves at 8.00 x 106 m/s along the x-axis. It enters a region in which there is a magnetic
field of magnitude 2.50 T,...(Solved)
A proton moves at 8.00 x 106 m/s along the x-axis. It enters a region in which there is a magnetic
field of magnitude 2.50 T, directed at an angle of 60.0° with the x-axis and lying in the xy - plane
(Fig. 4.3). Find the initial magnitude and direction of the magnetic force on the proton.
Date posted: May 12, 2021. Answers (1)
- The Earth's magnetic field is about 50 µT northward. Find the velocity that an electron moving
westward would have so that the magnetic force balances gravity.(Solved)
The Earth's magnetic field is about 50 μT northward. Find the velocity that an electron moving
westward would have so that the magnetic force balances gravity.
Date posted: May 12, 2021. Answers (1)
- A +10 µC charge moves from left to right at a speed of 5 x 106 m/s. There is a 0.04 T magnetic
field toward one...(Solved)
A +10 μC charge moves from left to right at a speed of 5 x 106 m/s. There is a 0.04 T magnetic
field toward one o'clock, if the page were a clock. Find the magnetic force on the charge.
Date posted: May 12, 2021. Answers (1)
- Show that the energy stored in a capacitor is(Solved)
Show that the energy stored in a capacitor is 
Date posted: May 12, 2021. Answers (1)
- Derive an expression for the potential difference across the capacitor during the discharging process.(Solved)
Derive an expression for the potential difference across the capacitor during the discharging process.
Date posted: May 12, 2021. Answers (1)
- Obtain an expression showing the relationship between current and time during the discharging process.(Solved)
Obtain an expression showing the relationship between current and time during the discharging process.
Date posted: May 12, 2021. Answers (1)
- A battery, a capacitor and a resistor are connected as shown in figure below. Obtain an expression
for the charge after the switch is closed.
When switch...(Solved)
A battery, a capacitor and a resistor are connected as shown in figure below. Obtain an expression
for the charge after the switch is closed.
When switch is closed at 1, capacitor charging and when at position 2, the capacitor is
discharging.
Date posted: May 12, 2021. Answers (1)
- An uncharged capacitor of capacitance 25 µF is connected to a circuit containing a switch and a
battery which provides a potential difference of 120 V....(Solved)
An uncharged capacitor of capacitance 25 μF is connected to a circuit containing a switch and a
battery which provides a potential difference of 120 V. How much charge will pass through the
capacitor after the switch is closed?
Date posted: May 12, 2021. Answers (1)
- Obtain the current-voltage relationship of a capacitor.(Solved)
Obtain the current-voltage relationship of a capacitor.
Date posted: May 12, 2021. Answers (1)
- Four capacitors are connected in series with a battery, as in figure below.
(a) Calculate the capacitance of the equivalent capacitor.
(b) Compute the charge on the...(Solved)
Four capacitors are connected in series with a battery, as in figure below.
(a) Calculate the capacitance of the equivalent capacitor.
(b) Compute the charge on the 3 μF capacitor.
(c) Find the voltage drop across the 24 μF capacitor.
Date posted: May 12, 2021. Answers (1)
- Figure below shows four capacitors connected in parallel
(a) Determine the capacitance of the single capacitor that is equivalent to the parallel
combination of the capacitors, and
(b)...(Solved)
Figure below shows four capacitors connected in parallel
(a) Determine the capacitance of the single capacitor that is equivalent to the parallel
combination of the capacitors, and
(b) Find the charge on the 12.0 μF capacitor.
Date posted: May 12, 2021. Answers (1)
- A parallel-plate capacitor has an area A= 2.00 x 10-4 m2 and a plate separation d =1.00mm.
Find its capacitance.(Solved)
A parallel-plate capacitor has an area A= 2.00 x 10-4 m2 and a plate separation d =1.00mm.
Find its capacitance.
Date posted: May 12, 2021. Answers (1)
- A charge q1 = 2.00 µC is located at the origin, and a charge q2 = -6.00 µC is located at (0, 3.00)
m, as shown...(Solved)
A charge q1 = 2.00 μC is located at the origin, and a charge q2 = -6.00 μC is located at (0, 3.00)
m, as shown in figure a.
(a) Find the total electric potential due to these charges at the point P, whose coordinates are
(4.00, 0) m.
(b) Find the change in potential energy of a 3.00 μC charge as it moves from infinity to point P
of (Fig a) such that the situation is as in Fig b.
Date posted: May 11, 2021. Answers (1)
- Two large, parallel, conducting plates are 12 cm apart and have charges of equal magnitude and
opposite sign on their facing surfaces. An electrostatic force of...(Solved)
Two large, parallel, conducting plates are 12 cm apart and have charges of equal magnitude and
opposite sign on their facing surfaces. An electrostatic force of 3.9 x 10-15 N acts on an electron
placed anywhere between the two plates (Neglecting fringing)
(a) Find the electric filed at the position of the electron
(b) What is the potential difference between the plates?
Date posted: May 11, 2021. Answers (1)
- A rod of length l has a uniform positive charge per unit length ? and a total charge Q. Calculate the electric field at a...(Solved)
A rod of length l has a uniform positive charge per unit length λ and a total charge Q. Calculate the electric field at a point P that is located along the long axis of the rod and a distance a from one end.
Date posted: May 11, 2021. Answers (1)
- A charge q1 = 7.0 µC is located at the origin, and a second charge q2 = -5.0µC is located on the x
axis, 0.30 m...(Solved)
A charge q1 = 7.0 μC is located at the origin, and a second charge q2 = -5.0μC is located on the x
axis, 0.30 m from the origin. Find the electric field at the point P, which has coordinates (0, 0.40) m.
Date posted: May 11, 2021. Answers (1)