{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# lecture11 - Physics 102 Lecture 11 Generators and...

This preview shows pages 1–8. Sign up to view the full content.

Generators and Transformers Physics 102: Lecture 11 Verify ‘EX’ grades for Exam #1!

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

View Full Document
Review: Magnetic Flux φ is angle between normal and B B A φ n o rmal Φ = B A cos( φ29 Units is T m 2 = Wb
Review: Induction Faraday’s Law Magnitude of induced EMF given by: Lenz’s Law – If the magnetic flux ( Φ B ) through a loop changes, an EMF will be created in the loop to oppose the change in flux EMF current (V=IR) additional B-field. Flux decreasing => B-field in same direction as original Flux increasing => B-field in opposite direction of original 7 i f i f t t t - Φ - Φ - = ∆Φ - = ε

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

View Full Document
Review: Rotation Variables v, ϖ , f , T Velocity (v): How fast a point moves. Units: usually m/s Angular Frequency ( ϖ ): How fast something rotates. Units: radians / sec ϖ r v v ϖ = v / r f = ϖ / 2 π T = 1 / f = 2 π / ϖ Frequency ( f ): How fast something rotates. Units: rotations / sec = Hz Period (T): How much time one full rotation takes. Units: usually seconds 10
Generators and EMF ε loop = ϖ B A sin( ϖ t) Φ = BA cos( ϖ t) v v x θ ϖ r 1 2 13 ε t ϖ AB AB EMF is voltage! Φ = B A cos( θ ) = B A cos( ϖ t) ε loop = - ∆Φ / t = ϖ B A sin( θ ) = ϖ B A sin( ϖ t )

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

View Full Document
Generators and EMF v v x θ ϖ r 1 2 13 ε t ϖ AB AB EMF is voltage! Φ = B A cos( θ ) = B A cos( ϖ t) ε loop = - ∆Φ / t = ϖ B A sin( ϖ t ) flux is maximum when emf is 0 And vice versa Φ t - AB AB
ACT: Generators and EMF x ε

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.

{[ snackBarMessage ]}