Recent content by choco_moo

Homework Statement 1. A small bulb is placed in front of a convex lens. It is placed at one focal point of the lens. Draw at least five rays from the bulb that pass through the lens. Where is the lens located in this case? Explain. (Hint: How are the rays that have passed through the...

Ah, thank you Doc! that makes so much more sense now.

so, time 1 will have the greatest induced current, while time 2 will have the least induced current. therefore, will time 2 have zero current? would the direction of the current in time 1 be clockwise?

the angle is greatest at 90° since sin(90°) = 1. it is zero at 0°.

okay, so i have: Φ= BAcosθ dΦ/dθ = -BAsinθ

on the first diagram, the magnetic field and the plane of the loop are parallel to each other correct? so there must be zero flux. on the second diagram, the plane of the loop and magnetic field are perpendicular to each other so flux is at its maximum. is that right?

the magnetic field from the magnet generates an emf that determines the induced current. induced current produces a magnetic field opposing the change in flux. if flux is increasing in some direction, then the current will produce a magnetic field that decreases the flux in that direction, and...

Homework Statement A metal loop is attached to an axle with a handle as shown. The north pole of a magnet is placed below the loop and the handle turned so that the loop rotates counterclockwise at a constant angular speed. On the two diagrams below, indicate the direction of the induced...

This time I tried using negatives for my answers and guess what, they're right! So this whole time, it was a sign problem. However, I don't really understand why they're negative. Can you explain why?

Homework Statement A conducting rod is pulled horizontally with constant force F= 3.40 N along a set of rails separated by d= 0.260 m. A uniform magnetic field B= 0.500T is directed into the page. There is no friction between the rod and the rails, and the rod moves with constant velocity v=...

so for (b), if F must be perpendicular to B, then would F be pointing out of the page? in (c), would B be going in the opposite direction (upward-leftward)? If so, would the wire be at (3, 5)?

Homework Statement Shown at right is a cross-sectional view of two long straight wires that are parallel to one another. One wire carries a current out of the page; the other carries an equal current into the page. I don't know how to show the diagrams, but the current into the page is at...

Homework Statement A compass needle points 19.1 degrees E of N outdoors. However, when it is placed 9.80 cm to the east of a vertical wire inside a building, it points 55.7 degrees E of N. What is the magnitude of the current in the wire? The Earth's field there is 4.80×10-5 T and is...

So I figured out the answers: A) True, because of what you just stated. B) False, because the direction is always changing. The B-field is constantly moving. C) True, because of the right hand rule. -z is pointing into the page. D) False, because the B-field is always moving, so the...

Nevermind, I got it. It goes EHFB. My hand just wasn't working right.