1 Before you start: Have you done all the practice quizzes, including the one on sigificant figures? The quizzes do 1 point not count for marks, and some of the quiz questions are quite hard. The quizzes are for learning and these tests are for assessment. Because the course runs in on-demand mode, we cannot give solutions to the test questions. But the quizzes have solutions and feedback. So, if you have troubles with these test questions, you should go back to the relevant lesson and then do the relevant quiz to check your understanding. Important: In a hand-marked test an answer with the wrong number of significant figures, but otherwise correct would usually earn most of the marks for a question. However, this testing software does not allow for part marks. So we had to make a decision. if we give full marks for an answer that has the wrong number of significant figures, then we give the impression that sig figs are not important. 50, in most cases, we decided that to get the marks, you have to have the correct answer with the appropriate number of sig figs. We regularly give reminders about this. Please take the time to learn about sig figs and please be careful with these and all future questions. A FAQ. Are the answers and the marking algorithm correct? You can be sure that we have checked them thoroughly, and many students on the course have checked them, too. Two common mistakes are giving the wrong number of significant figures and not reading the answer format instructions. Another common mistake is simply being wrong! [#161] Circle question (an easy one to start) What is the circumference of a circle with a radius of 2.1 cm? Enter your answer as a number; do not include units. You must use the appropriate number of significant figures. If you have not done lesson 1.2 and practice quiz 1.2, you should go back to them before you go on. Circumference = _ cm. Enter answer here3. [#163] Sammy's height 1 point In the US, lengths are often measured in inches, feet, yards and miles. Let's do some conversions. The definition of the inch is: 1 inch = 25.4 mm, exactly. A foot is 12 inches and a mile is 5260 ft, exactly. A centimetre is exactly 0.01 m or 10 mm. Sammy is 5 feet and 5.3 inches tall. Mark all the true statements below (Hint: use the 'multiply by 1' technique. Use the appropriate number of sig figs.): Sammy is 1.66 m tall. OSammy is less than 0.5 m tall. Sammy is between 1600 and 1700 mm tall. Sammy is more than 168 cm tall Sammy is 55.3 inches tall OSammy is more than 60 inches tall Sammy is 5.44 feet tall Sammy is 5.4 feet tall It would take about 90000 Sammies, lying head to toe, to span the entire length of Victoria's 90-mile beach It would take over 100000 Sammies, lying head to toe, to span the entire length of Victoria's 90-mile beach4., [#164] Horsepower 1point A solar racing car" typically has a power of about 1.2 kW [1.2 kilowatts]. What is this in horsepower [hp]? [Use the conversion 1 hp = ?45.? watts]. For practice. write your answer formally using the 'multiply by 1' technique we've been using. Give your final answer as a number, with the appropriate number ofsr'g gs. Do NOT include units. 1.2 kW = horsepower. * For geeks, my blog on a 3000 km solar race across Australia is at_ h_ttp:ttnewt.mys.unsw.edu.auf~iwaunswift2009.html Enter answer here 5, [#165] Adding vectors 1point || = |f5| = ||. Further, 3 + E + (E = 0. What is the angle between A. and f5 ? Express your answer in degrees, but do not include units. Example: for 30 degrees. write "30". Important hint: draw one or two diagrams, with arrowheads on the vectors, and think carefully about what the angle between two vectors means. We also suggest [seriously] that you try acting it out: what path do you make if you change your velocity by say 30? By 180? To walk around a triangle and then to end up going in the original direction. what is the sum of the changes in direction you had to make? [If you get the wrong answer. come back and read these hints again.) 2. [#162] Density Density is defined as mass per unit volume. A solid cylinder has a diameter of 17.4 mm and a length of 50.3 mm. Its mass is 49 g. What is its density? Give your answer in metric tonnes per cubic metre. [The metric tonne is 'IUUU kg.) Enter your answer as a number. using the appropriate number ofsr'g gs. Do NOT include unitsf. Density = tonnes din3 * You may think it is odd that we ask you not to enter units: so do we! Unfortunately this is a limitation of the software. In the real world. and in high school and university tests. it is very important to identify units. so we have asked Coursera to fix this. Enter answer here [#163] Sammy's height In the US. lengths are often measured in inches. feet. yards and miles. Let's do some conversions. The definition of the inch is: 'I inch = 25.4 mm. exactly. Afoot is 12 inches and a mile is 5280 ft exactly. A centimetre is exactly 0.01 m or 10 mm. Sammy is 5 feet and 5.3 inches tall. Mark all the true statements below (Hint: use the 'multiply by I' technique. .I -. I .- r- 1 point 1 point