Magnetic Fields - AP Physics 2
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Determine the magnetic force on a wire if $I = 3 , A$, $L = 2 , m$, and $B = 0.5 , T$.
Determine the magnetic force on a wire if $I = 3 , A$, $L = 2 , m$, and $B = 0.5 , T$.
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3 N. Using $F = ILB$ for perpendicular orientation: $3 \times 2 \times 0.5$.
3 N. Using $F = ILB$ for perpendicular orientation: $3 \times 2 \times 0.5$.
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What is the formula for the cyclotron frequency of a charged particle?
What is the formula for the cyclotron frequency of a charged particle?
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$f = \frac{qB}{2\pi m}$. Frequency of circular motion in uniform magnetic field.
$f = \frac{qB}{2\pi m}$. Frequency of circular motion in uniform magnetic field.
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Find the magnetic field strength inside a solenoid with $n = 1000 , \text{turns/m}$ and $I = 0.01 , \text{A}$.
Find the magnetic field strength inside a solenoid with $n = 1000 , \text{turns/m}$ and $I = 0.01 , \text{A}$.
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$1.26 \times 10^{-5} \text{ T}$. Using $B = \mu_0 n I$ with given turn density and current.
$1.26 \times 10^{-5} \text{ T}$. Using $B = \mu_0 n I$ with given turn density and current.
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What is the principle behind the operation of a galvanometer?
What is the principle behind the operation of a galvanometer?
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Torque on a current loop in a magnetic field. Current loop rotates in magnetic field producing measurable deflection.
Torque on a current loop in a magnetic field. Current loop rotates in magnetic field producing measurable deflection.
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What is the formula for the magnetic force on a current-carrying wire?
What is the formula for the magnetic force on a current-carrying wire?
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$F = I(L \times B)$. Current $I$ and length $L$ replace charge and velocity in force equation.
$F = I(L \times B)$. Current $I$ and length $L$ replace charge and velocity in force equation.
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Find the magnetic field strength inside a solenoid with $n = 1000 , \text{turns/m}$ and $I = 0.01 , \text{A}$.
Find the magnetic field strength inside a solenoid with $n = 1000 , \text{turns/m}$ and $I = 0.01 , \text{A}$.
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$1.26 \times 10^{-5} \text{ T}$. Using $B = \mu_0 n I$ with given turn density and current.
$1.26 \times 10^{-5} \text{ T}$. Using $B = \mu_0 n I$ with given turn density and current.
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Which device uses magnetic fields to separate charged particles by mass?
Which device uses magnetic fields to separate charged particles by mass?
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Mass spectrometer. Different masses follow different curved paths in magnetic field.
Mass spectrometer. Different masses follow different curved paths in magnetic field.
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What is the formula for the magnetic force on a moving charge?
What is the formula for the magnetic force on a moving charge?
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$F = q(v \times B)$. Cross product shows force is perpendicular to both $v$ and $B$.
$F = q(v \times B)$. Cross product shows force is perpendicular to both $v$ and $B$.
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Identify the rule used to determine the direction of the magnetic force on a moving charge.
Identify the rule used to determine the direction of the magnetic force on a moving charge.
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Right-hand rule. Point fingers along $v$, curl toward $B$, thumb shows force direction.
Right-hand rule. Point fingers along $v$, curl toward $B$, thumb shows force direction.
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What is the definition of magnetic flux density?
What is the definition of magnetic flux density?
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Magnetic flux per unit area. Magnetic field $B$ represents flux density through a surface.
Magnetic flux per unit area. Magnetic field $B$ represents flux density through a surface.
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Choose the correct expression for the force between two parallel conductors carrying current.
Choose the correct expression for the force between two parallel conductors carrying current.
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$F/L = \frac{\mu_0 I_1 I_2}{2\pi d}$. Force per unit length between parallel current-carrying conductors.
$F/L = \frac{\mu_0 I_1 I_2}{2\pi d}$. Force per unit length between parallel current-carrying conductors.
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Which option correctly describes the Biot-Savart Law?
Which option correctly describes the Biot-Savart Law?
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It relates magnetic fields to the currents which produce them. Fundamental law connecting magnetic fields to their current sources.
It relates magnetic fields to the currents which produce them. Fundamental law connecting magnetic fields to their current sources.
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What is the formula for the magnetic force on a moving charge?
What is the formula for the magnetic force on a moving charge?
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$F = q(v \times B)$. Cross product shows force is perpendicular to both $v$ and $B$.
$F = q(v \times B)$. Cross product shows force is perpendicular to both $v$ and $B$.
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State the formula for the magnetic field inside a toroid.
State the formula for the magnetic field inside a toroid.
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$B = \frac{\mu_0 n I}{2\pi r}$. Toroidal geometry confines field within the torus structure.
$B = \frac{\mu_0 n I}{2\pi r}$. Toroidal geometry confines field within the torus structure.
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Identify the rule used to determine the direction of the magnetic force on a moving charge.
Identify the rule used to determine the direction of the magnetic force on a moving charge.
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Right-hand rule. Point fingers along $v$, curl toward $B$, thumb shows force direction.
Right-hand rule. Point fingers along $v$, curl toward $B$, thumb shows force direction.
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What is the principle behind the operation of a galvanometer?
What is the principle behind the operation of a galvanometer?
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Torque on a current loop in a magnetic field. Current loop rotates in magnetic field producing measurable deflection.
Torque on a current loop in a magnetic field. Current loop rotates in magnetic field producing measurable deflection.
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Identify the force direction if a proton moves south in a magnetic field pointing upwards.
Identify the force direction if a proton moves south in a magnetic field pointing upwards.
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West. Using right-hand rule: velocity south, field up gives force west.
West. Using right-hand rule: velocity south, field up gives force west.
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What is the value of the permeability of free space ($\mu_0$)?
What is the value of the permeability of free space ($\mu_0$)?
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$4\pi \times 10^{-7} , \text{T}\cdot\text{m/A}$. Fundamental constant relating magnetic field to current.
$4\pi \times 10^{-7} , \text{T}\cdot\text{m/A}$. Fundamental constant relating magnetic field to current.
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What is the formula for the magnetic field due to a long, straight current-carrying wire?
What is the formula for the magnetic field due to a long, straight current-carrying wire?
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$B = \frac{\mu_0 I}{2\pi r}$. Field decreases as $1/r$ with distance from wire.
$B = \frac{\mu_0 I}{2\pi r}$. Field decreases as $1/r$ with distance from wire.
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State the formula for the magnetic field at the center of a circular loop of wire.
State the formula for the magnetic field at the center of a circular loop of wire.
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$B = \frac{\mu_0 I}{2R}$. Field at center is half that of infinite solenoid.
$B = \frac{\mu_0 I}{2R}$. Field at center is half that of infinite solenoid.
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Identify the relationship between magnetic flux and magnetic field.
Identify the relationship between magnetic flux and magnetic field.
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$\Phi_B = B \cdot A \cdot \cos \theta$. Flux depends on field strength, area, and orientation angle.
$\Phi_B = B \cdot A \cdot \cos \theta$. Flux depends on field strength, area, and orientation angle.
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What is the definition of a Tesla?
What is the definition of a Tesla?
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1 Tesla = 1 N/(A·m). Force per unit current per unit length in magnetic field.
1 Tesla = 1 N/(A·m). Force per unit current per unit length in magnetic field.
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What is the relationship between magnetic moment and torque?
What is the relationship between magnetic moment and torque?
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$\tau = \mu \times B$. Torque is cross product of magnetic moment and field vectors.
$\tau = \mu \times B$. Torque is cross product of magnetic moment and field vectors.
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State the formula for the magnetic field at a point on the axis of a current loop.
State the formula for the magnetic field at a point on the axis of a current loop.
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$B = \frac{\mu_0 I R^2}{2(x^2 + R^2)^{3/2}}$. Field strength decreases rapidly with distance from loop center.
$B = \frac{\mu_0 I R^2}{2(x^2 + R^2)^{3/2}}$. Field strength decreases rapidly with distance from loop center.
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Calculate the magnetic field strength 1 m away from a 5 A current-carrying wire.
Calculate the magnetic field strength 1 m away from a 5 A current-carrying wire.
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$1 \times 10^{-6} \text{ T}$. Using $B = \frac{\mu_0 I}{2\pi r}$ with given values.
$1 \times 10^{-6} \text{ T}$. Using $B = \frac{\mu_0 I}{2\pi r}$ with given values.
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What is the formula for the Hall voltage in a conductor?
What is the formula for the Hall voltage in a conductor?
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$V_H = \frac{IB}{net}$. Hall effect: voltage across conductor in magnetic field.
$V_H = \frac{IB}{net}$. Hall effect: voltage across conductor in magnetic field.
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Identify the main factor that affects the magnitude of the magnetic force on a conductor.
Identify the main factor that affects the magnitude of the magnetic force on a conductor.
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Current (I). Force is directly proportional to current flowing through conductor.
Current (I). Force is directly proportional to current flowing through conductor.
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What is the direction of the magnetic force on a positive charge moving in a magnetic field?
What is the direction of the magnetic force on a positive charge moving in a magnetic field?
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Perpendicular to both velocity and magnetic field. Cross product in Lorentz force creates perpendicular direction.
Perpendicular to both velocity and magnetic field. Cross product in Lorentz force creates perpendicular direction.
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What is the formula for the magnetic torque on a current loop?
What is the formula for the magnetic torque on a current loop?
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$\tau = nIAB \sin \theta$. Torque depends on loop area $A$ and angle $\theta$ with field.
$\tau = nIAB \sin \theta$. Torque depends on loop area $A$ and angle $\theta$ with field.
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State the expression for the force on a moving charge in an electric and magnetic field.
State the expression for the force on a moving charge in an electric and magnetic field.
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$F = q(E + v \times B)$. Complete Lorentz force including both electric and magnetic components.
$F = q(E + v \times B)$. Complete Lorentz force including both electric and magnetic components.
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