AP Physics 2 Flashcards: Magnetism And Current Carrying Wires

What this deck covers

This deck focuses on Magnetism And Current Carrying Wires, giving you a quick way to review the definitions, rules, and examples that matter most for AP Physics 2.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: What is the direction of the force on a negative charge in a magnetic field?

Answer: Opposite to right-hand rule. Negative charge reverses the force direction from right-hand rule.

Flashcard 2: State the formula for the force between two parallel current-carrying wires.

Answer: $F = \frac{\mu_0 I_1 I_2 L}{2 \pi d}$. Force per unit length between parallel wires carrying current.

Flashcard 3: Calculate the force between two parallel wires $2 \text{ m}$ apart carrying $4 \text{ A}$ each.

Answer: $1.6 \times 10^{-6}$ N. Use force formula with $d=2m$ and $I_1=I_2=4A$.

Flashcard 4: What is the magnetic force direction on a wire with current in a magnetic field?

Answer: Perpendicular to both current and field. Force follows right-hand rule for current and field vectors.

Flashcard 5: State the formula for the magnetic field due to a moving point charge.

Answer: $B = \frac{\mu_0 q v \times \hat{r}}{4 \pi r^2}$. Moving charge creates magnetic field like current element.

Flashcard 6: State the unit of magnetic field strength.

Answer: Tesla (T). Tesla is the SI unit for magnetic field strength.

Flashcard 7: Calculate the magnetic force on a $2 \text{ C}$ charge moving at $3 \text{ m/s}$ perpendicular to a $4 \text{ T}$ field.

Answer: $24$ N. Use $F = qvB$ with perpendicular motion and field.

Flashcard 8: State the formula for the magnetic field due to a moving point charge.

Answer: $B = \frac{\mu_0 q v \times \hat{r}}{4 \pi r^2}$. Moving charge creates magnetic field like current element.

Flashcard 9: What happens to the magnetic field strength if the current in a wire doubles?

Answer: Doubles. Magnetic field is directly proportional to current.

Flashcard 10: What is the magnetic force on a charged particle moving parallel to a magnetic field?

Answer: Zero. No perpendicular component means no magnetic force.

Flashcard 11: Identify the unit for electric current.

Answer: Ampere (A). Ampere measures electric current flow rate.

Flashcard 12: What is the magnetic field direction around a long straight current-carrying wire?

Answer: Circular around the wire. Current creates concentric circular field lines around the wire.

Flashcard 13: Calculate the magnetic force on a $2 \text{ C}$ charge moving at $3 \text{ m/s}$ perpendicular to a $4 \text{ T}$ field.

Answer: $24$ N. Use $F = qvB$ with perpendicular motion and field.

Flashcard 14: What is the permeability of free space $\mu_0$ in Tm/A?

Answer: $4\pi \times 10^{-7}$ Tm/A. Fundamental constant relating magnetic field to current.

Flashcard 15: Find the magnetic field at the center of a loop with $5 \text{ A}$ and radius $0.1 \text{ m}$.

Answer: $10^{-5}$ T. Use $B = \frac{\mu_0 I}{2R}$ with given values.

Flashcard 16: What is the permeability of free space $\mu_0$ in Tm/A?

Answer: $4\pi \times 10^{-7}$ Tm/A. Fundamental constant relating magnetic field to current.

Flashcard 17: What is the effect of a magnetic field on an electron at rest?

Answer: No effect. Magnetic force requires motion of charged particle.

Flashcard 18: Find the magnetic force on a $2 \text{ m}$ wire with $3 \text{ A}$ current in $0.5 \text{ T}$ field.

Answer: $3$ N. Use $F = ILB$ with $I=3A$, $L=2m$, $B=0.5T$.

Flashcard 19: What fundamental quantity creates a magnetic field in a wire?

Answer: Electric current. Moving charges (current) generate magnetic fields.

Flashcard 20: State the formula for the magnetic field inside a solenoid.

Answer: $B = \mu_0 n I$. Field depends on turns per length and current.

Flashcard 21: Find the magnetic dipole moment of a $10$-turn coil with $2 \text{ A}$ current and $0.5 \text{ m}^2$ area.

Answer: $10 \text{ A m}^2$. Use $\mu = NIA$ with $N=10$, $I=2 \text{A}$, $A=0.5 \text{m}^2$.

Flashcard 22: What is the magnetic force on a charged particle moving parallel to a magnetic field?

Answer: Zero. No perpendicular component means no magnetic force.

Flashcard 23: What is the torque on a current loop in a uniform magnetic field?

Answer: $\tau = \mu B \sin(\theta)$. Torque depends on magnetic moment and field angle.

Flashcard 24: State the Biot-Savart Law for a small segment of current-carrying wire.

Answer: $dB = \frac{\mu_0}{4\pi} \frac{I \, d\ell \times \hat{r}}{r^2}$. Fundamental law for calculating magnetic fields from current elements.

Flashcard 25: Determine the magnetic force on a $0.5 \text{ C}$ charge moving at $4 \text{ m/s}$ in a $1 \text{ T}$ field.

Answer: $2$ N. Use $F = qvB$ with $q=0.5C$, $v=4m/s$, $B=1T$.

Flashcard 26: State the formula for the magnetic field at the center of a circular loop.

Answer: $B = \frac{\mu_0 I}{2R}$. Field at center depends on current and radius.

Flashcard 27: State the formula for the magnetic field at the center of a circular loop.

Answer: $B = \frac{\mu_0 I}{2R}$. Field at center depends on current and radius.

Flashcard 28: State the formula for the force between two parallel current-carrying wires.

Answer: $F = \frac{\mu_0 I_1 I_2 L}{2 \pi d}$. Force per unit length between parallel wires carrying current.

Flashcard 29: Identify the relationship between current direction and magnetic field in a wire.

Answer: Right-hand grip rule. Curl fingers in current direction, thumb points along magnetic field.

Flashcard 30: State the unit of magnetic field strength.

Answer: Tesla (T). Tesla is the SI unit for magnetic field strength.

Flashcard 31: Find the magnetic field at the center of a loop with $5 \text{ A}$ and radius $0.1 \text{ m}$.

Answer: $10^{-5}$ T. Use $B = \frac{\mu_0 I}{2R}$ with given values.

Flashcard 32: State the formula for the magnetic dipole moment of a coil.

Answer: $\mu = NIA$. Product of turns, current, and loop area.

Flashcard 33: Determine the magnetic force on a $1 \text{ C}$ charge moving at $2 \text{ m/s}$ in a $3 \text{ T}$ field.

Answer: $6$ N. Use $F = qvB$ with $q=1C$, $v=2m/s$, $B=3T$.

Flashcard 34: What is the relationship between magnetic field strength and distance from a wire?

Answer: Inversely proportional. Field strength decreases as $\frac{1}{r}$ from the wire.

Flashcard 35: What is the magnetic force direction on a wire with current in a magnetic field?

Answer: Perpendicular to both current and field. Force follows right-hand rule for current and field vectors.

Flashcard 36: Calculate the magnetic force on a wire with $3 \text{ A}$ current and $1 \text{ m}$ length in a $2 \text{ T}$ field.

Answer: $6$ N. Use $F = ILB$ with perpendicular orientation.

Flashcard 37: What is the formula for the magnetic force on a current-carrying wire?

Answer: $F = I L B \, \sin(\theta)$. Force equals current times length times magnetic field times sine of angle.

Flashcard 38: What is the torque on a current loop in a uniform magnetic field?

Answer: $\tau = \mu B \sin(\theta)$. Torque depends on magnetic moment and field angle.

Flashcard 39: What is the direction of the magnetic field inside a solenoid?

Answer: Parallel to the axis. Solenoid creates uniform field along its central axis.

Flashcard 40: What is the effect of doubling the velocity of a charged particle on the magnetic force it experiences?

Answer: Doubles the force. Force is directly proportional to particle velocity.

Flashcard 41: What is the magnetic field direction around a long straight current-carrying wire?

Answer: Circular around the wire. Current creates concentric circular field lines around the wire.

Flashcard 42: What is the relationship between magnetic field strength and distance from a wire?

Answer: Inversely proportional. Field strength decreases as $\frac{1}{r}$ from the wire.

Flashcard 43: What is the effect of doubling the velocity of a charged particle on the magnetic force it experiences?

Answer: Doubles the force. Force is directly proportional to particle velocity.

Flashcard 44: What fundamental quantity creates a magnetic field in a wire?

Answer: Electric current. Moving charges (current) generate magnetic fields.

Flashcard 45: Determine the magnetic force on a $0.5 \text{ C}$ charge moving at $4 \text{ m/s}$ in a $1 \text{ T}$ field.

Answer: $2$ N. Use $F = qvB$ with $q=0.5C$, $v=4m/s$, $B=1T$.

Flashcard 46: What is the direction of the force on a negative charge in a magnetic field?

Answer: Opposite to right-hand rule. Negative charge reverses the force direction from right-hand rule.

Flashcard 47: Determine the force on a $1.5 \text{ m}$ wire with $4 \text{ A}$ current parallel to a $0.2 \text{ T}$ field.

Answer: $0$ N. Parallel orientation gives $\sin(0°) = 0$, so no force.

Flashcard 48: Calculate the magnetic force on a wire with $3 \text{ A}$ current and $1 \text{ m}$ length in a $2 \text{ T}$ field.

Answer: $6$ N. Use $F = ILB$ with perpendicular orientation.

Flashcard 49: Find the magnetic dipole moment of a $10$-turn coil with $2 \text{ A}$ current and $0.5 \text{ m}^2$ area.

Answer: $10$ Am$^2$. Use $\mu = NIA$ with $N=10$, $I=2A$, $A=0.5m^2$.

Flashcard 50: What is the formula for the magnetic force on a current-carrying wire?

Answer: $F = I L B \, \sin(\theta)$. Force equals current times length times magnetic field times sine of angle.

Flashcard 51: What is the direction of the magnetic force on a positive charge moving in a magnetic field?

Answer: Right-hand rule. Point fingers in velocity direction, curl toward field, thumb shows force.

Flashcard 52: What is the direction of the magnetic force on a positive charge moving in a magnetic field?

Answer: Right-hand rule. Point fingers in velocity direction, curl toward field, thumb shows force.

Flashcard 53: What is the direction of the magnetic field inside a solenoid?

Answer: Parallel to the axis. Solenoid creates uniform field along its central axis.

Flashcard 54: What is the effect on the magnetic field if the number of turns in a solenoid is doubled?

Answer: Doubles. Field strength is directly proportional to number of turns.

Flashcard 55: What happens to the magnetic field strength if the current in a wire doubles?

Answer: Doubles. Magnetic field is directly proportional to current.

Flashcard 56: Determine the force on a $1.5 \text{ m}$ wire with $4 \text{ A}$ current parallel to a $0.2 \text{ T}$ field.

Answer: $0$ N. Parallel orientation gives $\sin(0°) = 0$, so no force.

Flashcard 57: State the Biot-Savart Law for a small segment of current-carrying wire.

Answer: $dB = \frac{\mu_0}{4\pi} \frac{I \, d\ell \times \hat{r}}{r^2}$. Fundamental law for calculating magnetic fields from current elements.

Flashcard 58: What is the effect on the magnetic field if the number of turns in a solenoid is doubled?

Answer: Doubles. Field strength is directly proportional to number of turns.

Flashcard 59: Identify the relationship between current direction and magnetic field in a wire.

Answer: Right-hand grip rule. Curl fingers in current direction, thumb points along magnetic field.

Flashcard 60: What is the effect of temperature on the magnetization of ferromagnetic materials?

Answer: Decreases with increasing temperature. Higher temperature reduces magnetic alignment in ferromagnets.

Flashcard 61: State the formula for the magnetic field inside a solenoid.

Answer: $B = \mu_0 n I$. Field depends on turns per length and current.

Flashcard 62: Calculate the force between two parallel wires $2 \text{ m}$ apart carrying $4 \text{ A}$ each.

Answer: $1.6 \times 10^{-6}$ N. Use force formula with $d=2m$ and $I_1=I_2=4A$.

Flashcard 63: Find the magnetic force on a $2 \text{ m}$ wire with $3 \text{ A}$ current in $0.5 \text{ T}$ field.

Answer: $3$ N. Use $F = ILB$ with $I=3A$, $L=2m$, $B=0.5T$.

Flashcard 64: State the formula for the magnetic dipole moment of a coil.

Answer: $\mu = NIA$. Product of turns, current, and loop area.

Flashcard 65: What is the effect of temperature on the magnetization of ferromagnetic materials?

Answer: Decreases with increasing temperature. Higher temperature reduces magnetic alignment in ferromagnets.

Flashcard 66: Determine the magnetic force on a $1 \text{ C}$ charge moving at $2 \text{ m/s}$ in a $3 \text{ T}$ field.

Answer: $6$ N. Use $F = qvB$ with $q=1C$, $v=2m/s$, $B=3T$.

Flashcard 67: What is the effect of a magnetic field on an electron at rest?

Answer: No effect. Magnetic force requires motion of charged particle.