final true or false

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Magnetic force on a moving charged particle provides an acceleration to the particle. Thus, it also changes the kinetic energy of the particle.

false

Parallel conducting wires carrying currents in the same direction repel each other.

false

The Kirchhoff's junction rule is based on the conservation of energy.

false

The Kirchhoff's loop rule is based on the conservation of charge.

false

The current in an LC circuit oscillates at the frequency f =1/(2π LC).

false

The drift speed of electrons in a copper wire is much greater than 1 mm/sec

false

The electrostatic potential generated by multiple charges, is the vector addition of the potentials generated by individual charges.

false

The elementary charge equals 1.6 x 10-9 C.

false

The energy density in an electric field is proportional to the cubic of the magnitude of the electric field at a given point.

false

The equivalent resistance of a parallel combination of resistors is always greater than any of the individual resistors

false

The index of refraction indicates the ability of a medium to bend the light beam as refraction occurs.

false

The instantaneous speed of charge carriers in a metal cannot be much higher than their "drift speed".

false

The magnetic field inside a toroid is uniform.

false

The magnetic force acting on a current-carrying conductor equals the sum of the forces exerted on all charges moving with a "drift velocity" inside the conductor.

false

The magnetic force exerted on a moving positive charge is in the same direction of the magnetic field B.

false

The magnitude of induced emf (or electric field) is inversely proportional to the time rate of changes of magnetic flux through the circuit.

false

The magnitude of work required to bring a charge q from point A to point B is |qVBA|.

false

The reason that a prism can produce a colorful spectrum from a white light source is that its index of refraction is a function of light frequency.

false

The resistance of a typical metal has a negative temperature coefficient.

false

The speed of light is the same in all optical mediums.

false

The time constant of an RC circuit is τ = 1/RC.

false

The time constant of an RL circuit is R/L.

false

Total internal reflection can occur when light travels from vacuum to an optical medium with higher index of refraction

false

When a light beam of wavelength λ is incident on a slit of width d, the ray approximation is valid when λ ≈ d.

false

eV is a unit for potential.

false, it is a unit of energy

At electrostatic equilibrium, the electric field is zero everywhere inside a conductor, and any charge can only be distributed on the surface of the conductor.

true

Capacitors are devices that store electric charges.

true

Changing magnetic flux can induce an emf in a circuit.

true

Constructive interference occurs when two or more waves overlap and the amplitude of the resultant wave is greater than that of any individual waves.

true

Converging lenses have positive focal lengths, and diverging lenses have negative focal lengths.

true

Depending on where the object is placed, the images formed by a converging lens can either be real and inverted or virtual and upright.

true

Due to the oscillations of current and charge in an LC circuit, the total energy of the system also oscillates.

true

Electric field vector is tangent to the electric field line at each point.

true

Electric flux can be understood as the number of electric field lines passing through a surface

true

Even if you can clearly see the bottom of a swimming pool, you usually underestimate the depth of the pool.

true

For an ideal solenoid, the interior magnetic field is uniform and the exterior field is zero.

true

For an image formed by a converging lens, if the object and the image have exactly the same size, the object distances must be twice of the focal length, so does the image distance.

true

For reflection of light, the angle of reflection equals the angle of incidence.

true

Gauss's law is useful for calculating electric field when the charge distribution is highly symmetrical.

true

Gauss's law of magnetism states that the net magnetic flux through any closed surface is zero.

true

If a charged particle moving in a straight horizontal line in a velocity selector, the magnitude of the electric force acting on the particle is equal to that of the magnetic force.

true

In Young's double-slit experiment, the condition for constructive interference is that the path difference of two waves must be either zero or some integer multiple of the wavelength.

true

Inductance is a measure of how much opposition an electric device offers to a change in current passing through the device.

true

Lenz's law is used to determine the direction of the induced emf or current.

true

Magnetic field lines, generated by a long straight wire carrying a current, are circles concentric with the wire and lie in planes perpendicular to the wire.

true

Magnetic fields are produced either by electric currents or time- varying electric fields.

true

Magnetic fields can be produced by electric currents.

true

Maxwell's equations predicted the existence of electromagnetic (EM) waves that propagate through space at the speed of light.

true

Maxwell's four equations, together with the Lorentz force law, give a complete description of all classical electromagnetic interactions.

true

No two electric field lines can cross or touch.

true

Optical fibers rely on total internal reflection to prevent light lose at the surfaces of the fibers.

true

The capacitance of a capacitor increases, when the region between the plates is filled with a dielectric material.

true

The capacitance of a parallel-plate capacitor is proportional to the area of its plates and inversely proportional to the plate separation.

true

The direction of flow of electrons is opposite the direction of the current.

true

The direction of magnetic force is perpendicular both to the velocity of the particle and to the magnetic field.

true

The electric and magnetic components of a plane EM wave are always perpendicular to each other.

true

The electric fields created by a point charge, a conducting sphere, and an insulator sphere are identical, if they all have the same amount of charge and the field is measured outside the spheres.

true

The electric power dissipated in a resistor is converted to thermal heat.

true

The electrostatic potential difference between point A and B, ∆VAB, can be calculated using a path integral, and ∆VAB does not depend on the integral path used.

true

The energy density of a magnetic field at a given point is given by: uB = B2 / 2μ0

true

The energy in an LC circuit continuously transfers between electric field energy stored in the capacitor and magnetic field energy stored in the inductor.

true

The equivalent capacitance of a parallel combination of capacitors is always greater than any of the individual capacitance.

true

The equivalent capacitance of a series combination of capacitors is always less than any individual capacitance in the combination.

true

The force on a negative charge is in the opposite direction of the electric field.

true

The frequency of a light ray is the same when the light travels from one medium to another.

true

The fundamental source of EM radiation is accelerating of charged particles.

true

The net magnetic force acting on any closed current-carrying loop in a uniform magnetic field is zero

true

The rate of flow of energy crossing a unit area is given by the Poynting vector.

true

Unlike electric field lines, magnetic field lines are continuous and always form closed loops.

true

When a charged particle is accelerated from rest in an electric field, the amount of kinetic energy increased equals the amount of potential energy decreased, i.e., |1/2 mv^|= |qΔV|

true

When an electric current flows through a conducting wire, the electric field and charge carrier density inside the conducting wire are no longer zero.

true

When charging a capacitor, the current decreases to 0.368 (i.e., 1/e) of its initial maximum value at time = 1 time constant.

true

When you see a fish in water from a boat, the fish is actually not at where you think it is.

true

An equipotential surface is always parallel to electric field lines.

False, it is perpendicular to electric field lines.

An electric field line points to the direction of higher electric potential.

False, it points to the direction of lower electric potential.

At any point P, the total electric field due to a group of point charges equals the vector sum of the electric fields of the individual charges.

True

A large, steady magnetic flux through a circuit induces a large emf.

false

A proton carries positive charge, and weights the same as an electron.

false

An induced electric field is a conservative field, just like a static electric field.

false

At least three rays of light are needed in order to find out where the image is formed.

false

At t = 1 time constant, the current in an RL circuit reaches to 63.2% of its final value.

false

Electric field just outside a charged conductor is perpendicular to the surface and has a magnitude σ/2ε0.

false

Every magnet has two poles: positive and negative poles.

false

For a concave mirror, if the object distance is less than R, the image is virtual, upright, and enlarged.

false

For a concave mirror, the center of curvature is also the focal point.

false

For a plane EM wave, the energy density of the electric field is larger than that of the magnetic field.

false

Gauss's law states that the net electric flux ΦE through any closed Gaussian surface is equal to the net charge inside the surface divided by 4πε0

false

If a moving charge does not experience any magnetic force, it can be concluded that the magnetic field must be zero in that region.

false

If an object is located at the focal point of a mirror or lens, no image forms

false

Inside a conductor, the electric field and potential are both zero.

false

Lenz's law states that the induced current and induced emf in a conductor are in such a direction as to enhance the magnetic flux change that produced them.

false

Like a sound wave, propagation of EM waves requires air as a medium.

false

A 10 μF capacitor can store 10 μC of charge for each volt of potential difference between the two conducting plates.

true

A common reference point for electrostatic potential is V = 0 at ∞

true

A healthy battery has a small internal resistance, and a weak battery has a large internal resistance.

true

A motional emf could be generated within a piece of a conductor, as the conductor moves through a uniform magnetic field.

true

A virtual image is one in which light rays do not converts to the image point but appear to emanate from that point

true

Although one can electrify a glass rod by rubbing it with silk, no net charge is created.

true

An electric field is induced by a changing magnetic flux, even in free space, without a conductor.

true

An inductor stores energy in the form of magnetic field.

true


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