# AT Cycle 30

## 3/11 - 3/16

F 3/11

M 3/14

T 3/15

W 3/16

### π΄β 1: F 3/11, π‘β 3: F 3/11 - magnetism assessment

Unit Assessment on all of Magnetism Today!

Homework: Make sure you have reviewed all of the induction topics you should have learned last year on my AT Induction Review page.

### π₯ 1: T 3/15 lab, π¨ 3: M 3/14 lab - Lenz's Law & Faraday's Law Review

NJ GPA Testing

Test - 7:40 - 9:40 (120)
1 - 9:45 - 10:31 (46)
2 - 10:36 - 11:12 (36)
3 - 11:17 - 11:53 (36)
4/L - 11:58 - 12:44/39 (46/41)
L/4 - 12:49/44 - 1:30 (41/46)
5 - 1:35 - 2:10 (35)
6 - 2:15 - 2:50 (35)

Today, we'll review Lenz's Law (presentation). We'll briefly discuss ways of inducing a current in a loop of wire. We'll review Lenz's Law which states, "An induced emf gives rise to a current whose magnetic field opposes the original change in flux." We'll see how we might use this concept to generate electricity to power a lightbulb. Practice at least one from each page on the Lenz's Law Practice page below.

Lenz's Law Practice Numbered.pdf

Then, we'll explore Faraday's Law with simulations and video demonstrations. Record your observations for each simulation/demonstration in βοΈ Google Classroom by Wednesday at 10pm.

INVESTIGATION 1:

What happens when a magnet moves through a coil in which a current can flow?

Move the magnet at a relatively constant frequency back and forth through the coil. The voltage displayed is proportional to the current flowing in the coil. Watch the reading of the voltmeter. What happens

• as you move the magnet through the coils with different number of loops,

• as you change the frequency and therefore the speed of the magnet for a given number of loops, and

• as you change the polarity of the magnet?

INVESTIGATION 2:

Using the window called Pickup Coil, investigate what you can about induction. Make a list of variables that affect the amount and direction of the induced current. Qualitatively describe how these variables affect the amount and direction of the induced current. Upload your explanation to βοΈ Google Classroom by Wednesday at 10pm.

INVESTIGATION 3:

Watch this video of Faraday's Law - Demonstrated & Explained. Using your own words and diagrams, explain the demonstration that starts at 2:57. Upload your explanation to βοΈ Google Classroom by Wednesday at 10pm.

INVESTIGATION 4 (optional but suggested):

With any time remaining, watch this video on Lenz's Law demonstrations, and explain at least what you observe in the demo from 1:00-3:02. Upload your explanation to βοΈ Google Classroom by Wednesday at 10pm. If you still have time, watch and try to make sense of the other demonstrations in this video.

Homework: Quiz on Induction Review on Thursday, March 17th. Finish all of the above in βοΈ Google Classroom by Wednesday at 10pm. Also, watch the following video on Faraday's Law of Induction. This video builds on the basics from last year, but gives some more details about computing induced current.

### β€οΈ 1: W 3/16, π 3: T 3/15 - Faraday's Law problems

NJ GPA Testing

Test - 7:40 - 9:40 (120)
1 - 9:45 - 10:31 (46)
2 - 10:36 - 11:12 (36)
3 - 11:17 - 11:53 (36)
4/L - 11:58 - 12:44/39 (46/41)
L/4 - 12:49/44 - 1:30 (41/46)
5 - 1:35 - 2:10 (35)
6 - 2:15 - 2:50 (35)

Daily check-in: magnetic flux with calculus

Today, you'll work on some problems from the textbook Chapter 30 involving Faraday's Law:

Required: Ch 30 Questions #11, 12, Problems #2, 3, 7, 12, 13, 17, 18, 26, 96
Enrichment 26, 27, 28

Homework: Reminder Faraday's Law βοΈ Google Classroom assignment due Wednesday at 10pm. Quiz on Induction Review on Thursday, March 17th. Watch the following video on the emf induced in a moving conductor. (If you need more information on how to derive the formula Ξ΅ = BLv, check your textbook Section 30-2 or look at the picture of the excerpt from Giancoli below the video.):

Here are a couple other videos from last year that you may want to review on motional emf: