{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# Lect22 - Physics 212 Lecture 21 Slide Physics 212 Lecture...

This preview shows pages 1–7. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 1 Physics 212 Physics 212 Lecture 22 Lecture 22 10 20 30 40 Avg Avg = 2.6 = 2.6 Confused Confused Confident Confident Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 2 What We Knew Before Prelecture 22 06 06 Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 3 Q E A σ ε ε = = After After Prelecture Prelecture 21: Modify Ampere 21: Modify Ampere ’ ’ s Law s Law 10 10 E Q EA ε Φ = = E Q ε = Φ E d dQ dt dt ε Φ = E D d dQ I dt dt ε Φ = ≡ Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 4 Displacement Current Displacement Current Real Current: Charge Q passes through area A in time t: Displacement Current: Electric flux through area A changes in time dQ I dt = E D d I dt ε Φ = 08 Free space Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 5 Calculation Calculation Switch S has been open a long time when at t = 0, it is closed. Capacitor C has circular plates of radius R . At time t = t 1 , a current I 1 flows in the circuit and the capacitor carries charge Q 1 . At time t 1 , what is the magnetic field B 1 at a radius r ( point d ) in between the plates of the capacitor? S R a V C R r ● I 1 Q 1 d • Conceptual and Strategic Analysis • Charge Q 1 creates electric field between the plates of C • Charge¡Q 1 changing in time gives rise to a changing electric flux between the plates • Changing electric flux gives rise to a displacement current I D in between the plates • Apply (modified) Ampere’s law using I D to determine B 10 Physics 212 Lecture 21, Slide Physics 212 Lecture 21, Slide 6 Calculation Calculation Switch S has been open a long time when at t = 0, it is closed....
View Full Document

{[ snackBarMessage ]}

### Page1 / 21

Lect22 - Physics 212 Lecture 21 Slide Physics 212 Lecture...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online