HW 03 - saldana (avs387) – homework 03 – Turner –...

This preview shows pages 1–3. Sign up to view the full content.

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: saldana (avs387) – homework 03 – Turner – (56705) 1 This print-out should have 11 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 10.0 points The diagram shows an isolated, positive charge Q , where point B is twice as far away from Q as point A . + Q A B 10 cm 20 cm The ratio of the electric field strength at point A to the electric field strength at point B is 1. E A E B = 1 1 . 2. E A E B = 8 1 . 3. E A E B = 4 1 . correct 4. E A E B = 2 1 . 5. E A E B = 1 2 . Explanation: Let : r B = 2 r A . The electric field strength E ∝ 1 r 2 , so E A E B = 1 r 2 A 1 r 2 B = r 2 B r 2 A = (2 r ) 2 r 2 = 4 . 002 (part 1 of 3) 10.0 points Consider the setup shown in the figure be- low, where the arc is a semicircle with radius r . The total charge Q is negative, and dis- tributed uniformly on the semicircle. The charge on a small segment with angle Δ θ is labeled Δ q . x y------------------ Δ θ θ r x y I II III IV B A O Δ q is given by 1. Δ q = 2 Q π 2. Δ q = Q 3. Δ q = Q 2 π 4. Δ q = 2 π Q 5. Δ q = Q Δ θ 2 π 6. Δ q = π Q 7. Δ q = Q Δ θ π correct 8. Δ q = 2 Q Δ θ π 9. Δ q = Q π 10. None of these Explanation: The angle of a semicircle is π , thus the charge on a small segment with angle Δ θ is Δ q = Q Δ θ π . 003 (part 2 of 3) 10.0 points The magnitude of the x-component of the electric field at the center, due to Δ q , is given by 1. Δ E x = k | Δ q | r 2 2. Δ E x = k | Δ q | (cos θ ) r 3. Δ E x = k | Δ q | (sin θ ) r saldana (avs387) – homework 03 – Turner – (56705) 2 4. Δ E x = k | Δ q | r 2 5. Δ E x = k | Δ q | sin θ r 2 6. Δ E x = k | Δ q | (cos θ ) r 2 7. Δ E x = k | Δ q | cos θ r 2 correct 8. Δ E x = k | Δ q | sin...
View Full Document

This note was uploaded on 10/26/2010 for the course PHYS 56705 taught by Professor Turner during the Spring '10 term at University of Texas at Austin.

Page1 / 5

HW 03 - saldana (avs387) – homework 03 – Turner –...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online