quiz919 - Version 055/AADBD quiz919 Demkov (59910) This...

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

View Full Document Right Arrow Icon
Version 055/AADBD – quiz919 – Demkov – (59910) 1 This print-out should have 5 questions. Multiple-choice questions may continue on the next column or page – fnd all choices beFore answering. 001 10.0 points A boat moves through the water oF a river at 7 . 78 m / s relative to the water, regardless oF the boat’s direction. IF the current is ±owing at 5 . 15 m / s, how long does it take the boat to complete a trip consisting oF a 234 m displacement down- stream Followed by a 239 m displacement up- stream? 1. 482.096 2. 256.286 3. 219.423 4. 75.8412 5. 108.972 6. 115.74 7. 225.913 8. 201.502 9. 133.677 10. 302.569 Correct answer: 108 . 972 s. Explanation: Let v b be the velocity oF the boat relative to the water, and v w the velocity oF water relative to the shore. Take downstream as the positive direction. ²or the downstream trip, the current is speeding him up, so the velocity oF the boat relative to the shore is v d = v b + v w and the time is t d = x d v d = x d v b + v w ²or the upstream trip, the current is slowing him down, so the velocity oF the boat relative to the shore is v u = v b - v w and the time is t u = x u v
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 3

quiz919 - Version 055/AADBD quiz919 Demkov (59910) This...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online