A wire carries a positive current to the left in the plane of this screen. What is the direction of the magnetic field at a point near the top of the screen, still in the plane of the screen?

A flat, square surface with side length 3.40 cm is in the xy-plane at z = 0. Calculate the magnitude of the flux through this surface produced by a magnetic field B=(0.200 T)i+(0.300 T)j-(0.500 T)k .

An electron experiences a magnetic force of magnitude 4.60x10^-15 N when moving at an angle of 60.0° with respect to a magnetic field of magnitude 3.50x10^-3 T. Find the speed of the electron.

A particle with mass 1.81x10^-3 kg and a charge of 1.22x10^-8 C has, at a given instant, a velocity v=(3.00x10^4 m>s)j. What are the magnitude and direction of the particle's acceleration produced by a uniform magnetic field B=(1.63 T)i+(0.980 T)j?

Which option best completes the following sentence? If a magnet is carefully balanced, as in a compass, the north end of the magnet points roughly toward…

At what distance from a wire carrying a 10 Acurrent is the magnetic field strength equal to $50\mu \mathrm{T}$? This is the approximate value of the earth's magnetic field.

Two long parallel wires lie in the $xy$-plane, each carrying a $5.0$ A current in opposite directions. Wire 1 lies along the$y=3.0\mathrm{ cm}$ line and carries a current in the positive $x$-direction; wire 2 lies along the $y=0$ line and carries a current in the negative $x$-direction. What is the magnitude of the magnetic field at the point $\left(0\text{cm,}1\text{.5}\text{cm,}0\mathrm{ cm}\right)$?

Singly ionized (one electron removed) atoms are accelerated and then passed through a velocity selector consisting of perpendicular electric and magnetic fields. The electric field is 155 V/m and the magnetic field is 0.0315 T. The ions next enter a uniform magnetic field of magnitude 0.0175 T that is oriented perpendicular to their velocity. (a) How fast are the ions moving when they emerge from the velocity selector? (b) If the radius of the path of the ions in the second magnetic field is 17.5 cm, what is their mass?

A 150-g ball containing 4.00x10^8 excess electrons is dropped into a 125-m vertical shaft. At the bottom of the shaft, the ball suddenly enters a uniform horizontal magnetic field that has magnitude 0.250 T and direction from east to west. If air resistance is negligibly small, find the magnitude and direction of the force that this magnetic field exerts on the ball just as it enters the field.