{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

pracSoln

# pracSoln - Physics 21 Fall 2004 Solution to Practice...

This preview shows pages 1–2. Sign up to view the full content.

Physics 21 Fall, 2004 Solution to Practice Questions Some of these questions on optics have been adapted from questions on the Physics 21 final given at the end of the spring semester of 2004. Try to work them using only the equation sheet and the notes on optics that will be provided with the final. Problem 1. Consider the polarizers in this problem as “perfect.” After passing through the first polarizer, the electric field of a light wave is (in SI units) E = E 0 cos[6 . 0 × 10 15 t 2 . 0 × 10 7 x ] ˆ j , with E 0 = 2 . 0 × 10 4 V/m. (a) What are the frequency and wavelength of this wave? ω = 2 πf = 6 . 0 × 10 15 f = 9 . 5 × 10 14 Hz k = 2 π/λ = 2 . 0 × 10 7 λ = 3 . 1 × 10 7 m (b) A second polarizer is oriented at 60 to the first. What is the magnitude and direction of the elec- tric field after passing through this second polar- izer? z y 30 O 60 O E 0 E 1 E 2 The projection of E 0 on the axis of the second polarizer is E 1 = E 0 cos 60 = 1 × 10 4 V/m.

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 ]}