If we place a closed Gaussian surface around a magnet, what is the net magnetic flux through the surface? positive negative zero
In this section we considered a circular parallel-plate capacitor with a changing electric field. Which describes the induced magnetic field lines? They extend radially outward. They extend radially inward. They extend from the positive plate to the negative plate. They extend from the negative plate to the positive plate. They form rings that are concentric with the plates.
Which describes the displacement current in a capacitor? It matches the charging current during the charging and then has the same value after the charging is complete. It matches the charging current during the charging and then is zero after the charging is complete. It is less than the charging current during the charging and then has the same value after the charging is complete. It is less than the charging current during the charging and then is zero after the charging is complete. It is greater than the charging current during the charging and then has the same value after the charging is complete. It is greater than the charging current during the charging and then is zero after the charging is complete.
Which is true about the field inclination of Earth's magnetic field? It is the angle (left or right) between the field's direction and the geographic south. It is the angle (up or down) between a horizontal plane and the field's direction. It is the angle (left or right) between the field's direction and the geographic north.
Which describes a diamagnetic material? Each atom has a magnetic dipole moment only when placed in an external magnetic field. Each atom has a magnetic dipole moment but the vectors are randomly oriented when not in an external magnetic field. The magnetic dipole moments of some of the electrons are aligned even when not in an external magnetic field.
Which produces the magnetic field in an electromagnetic wave? the changing of the electric field with time along a perpendicular direction the changing of the electric field with time along a parallel direction the constant (nonchanging) electric field along a perpendicular direction the constant (nonchanging) electric field along a parallel direction
What is the direction of the Poynting vector of an electromagnetic wave? It is perpendicular to the direction of travel and parallel to the magnetic field vectors. It is perpendicular to the direction of travel and parallel to the electric field vectors. It is opposite the direction of travel. It is in the direction of travel.
Which is true about the radiation force of light shining on a surface? The force is greater if the light is absorbed instead of being reflected. The force is greater if the light reflects back along its incident path than in some other direction. The force is greater if the light is reflected in some direction other than back along the incident path.
When unpolarized light is incident on a polarizing sheet, what fraction of the intensity is transmitted by the sheet? 0% 25% 50% 75% 100% It depends on the orientation of the polarizing axis of the sheet.
A beam of red and blue light in glass is incident at 30∘ on the glass surface, with air on the other side. Which is true? The blue light is bent toward the normal more than the red light. The blue light is bent toward the normal less than the red light. The blue light is bent away from the normal more than the red light. The blue light is bent away from the normal less than the red light.
A radio signal is detected from a previously unknown star. The star is found to be 6.0×1016 m away. How long did it take the light to reach Earth? 2.0×108 years 6.3 years 3.1 years 5.0×107 years
Complete the following statement: The speed of light in a vacuum is larger for higher frequency electromagnetic waves. larger for short wavelength electromagnetic waves. a constant value everywhere in the universe. larger for higher energy electromagnetic waves. smaller for higher energy electromagnetic waves.
An unpolarized beam of light with an intensity of 8000 W/m2 is incident on two ideal polarizing sheets. If the emerging light has an intensity 0.300 times the original intensity of the incident beam, what is the angle between the two polarizers? 1.50 rad 0.685 rad 1.42 rad 0.305 rad
A polarized beam of light emerging from a single polarizer has an intensity of 8000 W/m2. If the beam of light incident on the polarizer was unpolarized, what was the intensity of the initial beam of light? 8000 W/m2 4000 W/m2 2000 W/m2 16000 W/m2
A small sphere is placed halfway between the poles of a horseshoe magnet. One side of the magnet is then enclosed by a small rectangular box which includes the sphere and one side of the magnet, but not the other side. The entire combination of magnet, sphere, and small box is then placed inside a large cube. Rank the amount of total magnetic flux through each container, in order of increasing flux. sphere, box, cube box, sphere, cube The net flux is the same through each container. cube, box, sphere
Why can a magnetic monopole not exist, assuming Maxwell's Equations are currently correct and complete? It would violate Faraday's Law. It would not produce any magnetic flux. It would require that a magnetic field exist in the presence of an electric field. If enclosed by a surface, it would produce a net flux through the surface.
While on a hike in the North Cascades National Park in the state of Washington, where the magnetic field declination is 17.0 degrees, you want to reach a campsite which is 11.0 km due north of your current position. You look at your compass, and walk 11.0 km in the direction the compass points but after walking the full distance, the campsite is nowhere in view. How far south are you from the campsite? km
What capacitance is needed to produce radio waves with a frequency of 2.1×107 Hz if the LC circuit contains an inductor with a inductance of 7.5×10−5 H ? 7.7×10−13 F 9.9×103 F 1.3×10−8 F 1.5×108 F
An unpolarized beam of light has an intensity of 3000 W/m2. It is incident on a single polarizing sheet. What is the intensity of light emerging from the polarizer? 1500 W/m2 6000 W/m2 750 W/m2 3000 W/m2
Maxwell's equations describe fields (electric and magnetic) and geometry. Maxwell's description of Gauss' Law for electric fields and Gauss' Law for magnetic fields both describe the flux of a field through a geometric surface. Gravity may also be described by a gravitational field, and there is a corresponding form of Gauss' Law for gravitational fields relating the flux of the gravitational field through a surface to the mass enclosed by that surface. If the gravitational field is defined as the force per unit mass experienced by a test mass, which one of Maxwell's equations does the gravitational form of Gauss' Law most resemble? Gauss' Law for electric fields, but with only positive "charge", since mass can't be negative. Gauss' Law for electric fields with mass dipoles replacing magnetic dipoles. Gauss' Law for magnetic fields with mass dipoles replacing magnetic dipoles. Gauss' Law for magnetic fields because there are no dipole masses.
In a stack of three polarizing sheets, the first and third are at right angles, while the middle one has its axis at an angle of 1.05 rad with respect to the first one. If an initially unpolarized beam of light with intensity 3000 W/m2 is incident on this stack of polarizers, what is the intensity of the emerging beam? 140 W/m2 647 W/m2 279 W/m2 1500 W/m2
The magnetic field declination at your location is 11.0 degrees east of north and the inclination is 47.0 degrees. If the magnitude of the Earth's magnetic field is 0.0600 mT at your location, how much current must flow in a long vertical wire placed 1.00 cm from the compass in order to make the compass point in the direction of geographic north? (Ignore the size of the compass compared to its distance from the wire and assume the compass is in a uniform magnetic field given by the value of the field 1.00 cm from the wire.) amperes.
A Gaussian surface in the shape of a right circular cylinder with end caps has a radius of 16.5 cm and a length of 120 cm . Through one end there is an inward magnetic flux of 20.6 μWb. At the other end there is a uniform magnetic field of 1.96 mT, normal to the surface and directed outward. What are the (a) magnitude and (b) direction (inward or outward) of the net magnetic flux through the curved surface? (a) Number Units (b)
A capacitor with parallel circular plates of radius R = 2.90 cm is discharging via a current of 11.5 A. Consider a loop of radius R/3 that is centered on the central axis between the plates. (a) How much displacement current is encircled by the loop? The maximum induced magnetic field has a magnitude of 16.0 mT. At what radius (b) inside and (c) outside the capacitor gap is the magnitude of the induced magnetic field 4.70 mT? (a) Number Units (b) Number Units (c) Number Units
A charge q = 5.0×10−7 C is distributed uniformly around a thin ring of radius r = 11 cm. The ring is rotating about an axis through its center and perpendicular to its plane, at an angular speed ω = 510 rad/s. What is the magnitude of the magnetic moment of the rotating charge? Number Units
The maximum electric field 12 m from a point light source is 3.0 V/m. What are (a) the maximum value of the magnetic field and (b) the average intensity of the light there? (c) What is the power of the source? (a) Number Units (b) Number Units (c) Number Units
A small spaceship whose mass is 2000 kg (including an astronaut) is drifting in outer space with negligible gravitational forces acting on it. If the astronaut turns on a 12 kW laser beam, what speed will the ship attain in 6.0 days because of the momentum carried away by the beam? Number Units
In the figure, a light ray in air is incident on a flat layer of material 2 that has an index of refraction n2 = 1.5. Beneath material 2 is material 3 with an index of refraction n3. The ray is incident on the air-material 2 interface at the Brewster angle for that interface. The ray of light refracted into material 3 happens to be incident on the material 2-material 3 interface at the Brewster angle for that interface. What is the value of n3? Number Units