Two bar magnets are placed side by side. Each magnet may swivel freely about a point in its center, and they align as shown in the diagram. One bar magnet has its south pole identified. What feature of the second bar magnet could be represented by the label X? A. the south pole, but not the north pole
A hiker walks in the direction that a compass needle points. In which location would the hiker’s direction deviate the most from geographic north? Assume that the compass needle is affected only by earth’s magnetic field.
C. within the Arctic Circle
How often, if ever, has earth’s magnetic field reversed its position?
C. a few times every million years
In the space around a permanent magnet, where is the magnetic field the strongest?
B. near the north and south poles of the magnet
Where is the magnetic field most nearly uniform?
D. between the flat, parallel magnetic poles of a C-shaped magnet
A proton enters a uniform magnetic field at a speed v. The magnetic field is oriented at an angle ϕ to the direction of the proton, and the strength of the field is B. Which change or set of changes would double the magnitude of the force on the proton?
A. doubling B
A proton is traveling with velocity through magnetic field . What is the direction of the force on the proton? Assume that you are viewing the diagram on a flat computer screen.
D. perpendicular to the screen, pointing toward you
As shown in the diagram, a proton is traveling at speed v as it enters a uniform magnetic field of strength B. The initial direction of the proton is toward the right of the screen. The field deflects the proton .
D. toward the bottom of the screen
As shown in the diagram, an electron is traveling at speed v as it enters a uniform magnetic field of strength B. The initial direction of the electron is toward the right of the screen. What are the magnitude and direction of the force on the electron? Let q equal the charge in coulombs on the electron.
A. magnitude |q|vB directed toward the top of the screen
velocity selector is built with a magnetic field of magnitude 5.2 T and an electric field of strength 4.6 × 104 N/C. The directions of the two fields are perpendicular to each other. At what speed will electrons pass through the selector without deflection? Let the charge of an electron q = −1.6 × 10−19 C.
A. 8.8 × 103 m/s