Tiêu đề Active PHYSICS DSE Level-up Companion 2.pdf ✅

✐ ✐ “DSE‐Companion” — 2020/5/27 — 12:24 — page 1 — #1 ✐ ✐ ✐ ✐ ✐ ✐ Answers and up-to-date information can be found at http://physics.pearson.com.hk. Contents Task 5A Average speed and velocity 2 Task 5B DSE inclined plane problems (I) 5 Task 5C Additional chapter-end questions 9 Task 6A Effect of static and dynamic friction 12 Task 6B Additional chapter-end questions 17 Task 7A Finding tension in accelerating system 18 Task 7B DSE inclined plane problems (II) 24 Task 7C Additional chapter-end questions 29 Task 8A Work done 37 Task 8B Additional chapter-end questions 40 Task 9A DSE possible collision problems 43 Task 9B Additional chapter-end questions 51 Task 10A Additional chapter-end questions 55 Task 11A Centripetal force and forces providing it 58 Task 11B Additional chapter-end questions 62 Task 12A Launching a satellite 65 Task 12B Additional chapter-end questions 69 For inspection © United Prime Educational Publishing (HK) Limited, Pearson Education Asia Limited 2023 All rights reserved; no part of this publication may be reproduced, photocopied, recorded or otherwise, without the prior written permission of the Publishers.
✐ ✐ “DSE‐Companion” — 2020/5/27 — 12:24 — page 2 — #2 ✐ ✐ ✐ ✐ ✐ ✐ VTo be used with Textbook After Ch. 5.2 Speed and velocity (p. 21) VBased on DSE results and Report comments 2020-1A Q4, 2018-1A Q7, 2017-1A Q5, 2016-1A Q4, 2015-1A Q4, Practice Paper-1A Q6 Level-up Task 5A Average speed and velocity Average speed and average velocity are confusing to many students. Answer the following questions to make sure you do not hold any misconceptions about them. True or false 1. Average speed and average velocity are the same thing except that velocity has direction but speed does not. ( true / false ) 2. The average speed of a car cannot be zero once it has moved. ( true / false ) 3. The average velocity of a car is zero when it completes a circle. ( true / false ) 4. The car that travelled a longer distance within the same period of time must have a greater average velocity. ( true / false ) 5. The car that took a longer time to complete the same path (from one place to another) must have a smaller average velocity. ( true / false ) For inspection © United Prime Educational Publishing (HK) Limited, Pearson Education Asia Limited 2023 All rights reserved; no part of this publication may be reproduced, photocopied, recorded or otherwise, without the prior written permission of the Publishers.
✐ ✐ “DSE‐Companion” — 2020/5/27 — 12:24 — page 3 — #3 ✐ ✐ ✐ ✐ ✐ ✐ Level-up Task 5A Average speed and velocity 3 6. For a car travelling at an increasing speed, its average speed must be equal to the average value of its initial speed and βinal speed. ( true / false ) Calculations 7. A car travelled 10 m due north in 5 s. After that, it immediately travelled 40 m due east in 10 s. (a) What was its average speed for the whole trip? (b) What was the magnitude of its average velocity for the whole trip? 8. A car travels due west at 3 m s−1 for 15 s, and then immediately travels due south at 2 m s−1 for 10 s. (a) Find the average speed of the car. For inspection © United Prime Educational Publishing (HK) Limited, Pearson Education Asia Limited 2023 All rights reserved; no part of this publication may be reproduced, photocopied, recorded or otherwise, without the prior written permission of the Publishers.