Magnetic Field Patterns and Earth's Magnetic Field

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At any location, the direction of the magnetic field B is the direction in which:

The south pole of a compass needle points

The magnetic field lines inside the magnet point towards

The magnetic field lines outside the magnet point towards

The north pole of a compass needle points (correct)

What symbol has historically been used to represent a magnetic field?

M

B (correct)

S

C

How can magnetic field lines of a bar magnet be traced according to the text?

By heating the bar magnet and observing the pattern

By observing the color changes on the bar magnet

By using a magnifying glass on the bar magnet

By means of drawings with magnetic field lines (correct)

When tracing the magnetic field lines of a bar magnet, where do the magnetic field lines outside the magnet point?

Away from the south pole (D) Signup and view all the answers

How can one display magnetic field patterns of a bar magnet, as shown in Figure 28.2?

Using small iron filings (B) Signup and view all the answers

Why is the north pole of a magnetic attracted toward the north geographic pole of Earth?

Because the south pole of the model bar magnet is near the north geographic pole (C) Signup and view all the answers

What is the relationship between the magnetic field lines and the magnetic field vector at any point?

The magnetic field vector is parallel to the field line. (D) Signup and view all the answers

How are the magnetic forces on oppositely charged particles moving at the same velocity in a magnetic field related?

They are in opposite directions. (A) Signup and view all the answers

What is the significance of the dashed lines in the figure?

They represent the paths of the particles being investigated. (C) Signup and view all the answers

According to the right-hand rule in Figure 28.5a, how can the direction of the cross product $\vec{v} \times \vec{B}$ be determined?

Point the four fingers of your right hand along the direction of $\vec{v}$, with the palm facing $\vec{B}$, and curl them toward $\vec{B}$. Your extended thumb points in the direction of $\vec{v} \times \vec{B}$. (B) Signup and view all the answers

What is the relationship between the magnetic force $\vec{F}_B$ and the cross product $\vec{v} \times \vec{B}$?

$\vec{F}_B = q(\vec{v} \times \vec{B})$ (C) Signup and view all the answers

What is the meaning of the magnetic field $\vec{B}$ at a given point in space?

It represents the force acting on a moving charged particle at that point. (B) Signup and view all the answers

What is the pattern of the magnetic field between opposite poles (NS) of two bar magnets?

The magnetic field lines form a continuous loop between the north and south poles. (B) Signup and view all the answers

What is the pattern of the magnetic field between like poles (NN) of two bar magnets?

The magnetic field lines form a divergent pattern between the magnets. (C) Signup and view all the answers

How does the Earth's magnetic field compare to the magnetic field of a bar magnet?

The Earth's magnetic field is more complex than a simple bar magnet, but still similar. (D) Signup and view all the answers

What happens to the orientation of a compass needle as it is moved northward?

The needle rotates so that it points more and more toward the Earth's surface. (C) Signup and view all the answers

What is the difference between the North magnetic pole and the North geographic pole?

The North magnetic pole is near the North geographic pole, but not exactly the same. (D) Signup and view all the answers

How has the position of the North magnetic pole changed over time?

The North magnetic pole has moved hundreds of miles since 1900. (C) Signup and view all the answers