A wire along the y-axis carries current in the +y-direction. In what direction is the magnetic field at a point on the +x-axis near the wire? (a) away from the wire
(b) vertically upward
(c) into the page
(d) out of the page

Video Transcript

This is College Physics Answers with Shaun Dychko. A wire carrying current in the positive y direction will create a magnetic field that is into the page on the x axis. You can verify that by grabbing this wire with your right hand and your thumb has to point in the direction of the current upwards towards the top of the page. Then when your fingers touch the positive x axis you'll see that they're pointing into the page. So this is the direction of the magnetic field due to the wire on the positive x axis.