Measurement, uncertainty and investigations

9.Which of the following is a vector quantity?

10.A student measures the length of a string as 15.6 cm. She then winds it closely around a pen 6 times. What is the circumference of the pen?

11.A force of 60 N acts to the right and a force of 100 N acts upward on an object. What is the magnitude of the resultant force?

12.An Olympic cyclist rides around a velodrome track 5 times. The stopwatch reads 2 s at the start (due to early start) and 1 min 22 s at the end. What is the average time per lap?

13.A student uses a ruler to measure the length of a metal rod. The ruler has markings every 1 mm. Which reading is recorded to the correct precision?

14.A student measures the time for 20 oscillations of a pendulum as 30.0 s. He then measures the time for 10 oscillations of the same pendulum as 15.2 s. Which measurement gives a more accurate value for the period, and why?

15.A student uses a measuring cylinder to measure the volume of a liquid. The bottom of the meniscus is at the 25 cm³ mark. The student's eye is above the meniscus. What is the most likely volume reading?

16.Which of the following quantities is a vector?

17.A student walks 3 km east and then 4 km north. What is the magnitude of the displacement?

18.A force of 30 N acts east and a force of 40 N acts north on an object. What is the magnitude of the resultant force?

19.A student measures the thickness of a single sheet of paper by measuring the thickness of a stack of 100 sheets with a ruler and dividing by 100. The ruler has millimetre markings. The stack thickness is measured as 1.2 cm. What is the thickness of one sheet?

20.A student wants to measure the volume of an irregularly shaped stone. Which apparatus is most suitable?

21.Which instrument is most suitable for measuring the length of a football field?

22.A student uses a stopwatch to time a runner over a 400 m track. The start time is 0:12.5 (12.5 s) and the finish time is 1:23.7 (1 minute 23.7 s). What is the time taken to complete the lap?

23.A student uses a ruler to measure the diameter of a ball-bearing. The ball-bearing is placed between two blocks on a ruler. The left block is at 2.0 cm and the right block is at 4.6 cm. What is the diameter of the ball-bearing?

24.A student measures the length of a string as 15.6 cm. She then winds it closely around a pen 6 times. What is the distance once round the pen?

25.A student uses a stopwatch to time 40 complete swings of a simple pendulum. The total time taken is 1 minute and 52 seconds. What is the period of the pendulum?

26.A boat travels 30 km due east and then 40 km due north. Which row correctly shows the total distance and displacement magnitude?

27.Three blocks X, Y, Z are placed into three measuring cylinders. The water level rises by 10 cm³ for X, 15 cm³ for Y, and 8 cm³ for Z. Which shows the blocks in order of increasing volume?

28.A person wishes to roast a chicken. The chicken requires 1 hour and 20 minutes in the oven to be properly cooked. The oven must be switched on 10 minutes before any food is put in, in order to pre-heat, and reach the correct temperature for cooking. The chicken needs to be ready at 4:30 pm. At what time must the oven be switched on?

29.An Olympic cyclist rides around a velodrome track 5 times. The stopwatch reads 2 s at the start (due to early start) and 1 min 22 s at the end. What is the average time to complete one lap?

30.A student uses a ruler to determine the circumference of a wooden dowel. She puts a mark onto the dowel, then rolls it along the ruler three times, before reading the position on the ruler at which it stopped. The initial mark aligns with 0 cm, and after three revolutions it aligns with 36.9 cm. What is the circumference of the dowel?

31.A student is timing the rate of cooling of a beaker of water. On a repeat run, the student forgets to zero the stopwatch. The start reading is 0:12.5 (12.5 s) and the end reading is 1:23.7 (1 min 23.7 s). How long did the cooling take?

32.A geologist wants to measure the volume of a pebble. She uses a measuring cylinder with water. The initial water level is 40 cm³. After adding the pebble, the water level is 57 cm³. What is the volume of the pebble?

33.Which instrument is most suitable for measuring the thickness of a single sheet of paper?

34.A student uses a ruler to determine the circumference of a wooden dowel. She puts a mark onto the dowel, then rolls it along the ruler three times, before reading the position on the ruler at which it stopped. The starting position is 0 cm and the final reading is 36.0 cm. What is the circumference of the dowel?

35.A geologist wants to measure the volume of a pebble. She uses a measuring cylinder with water. The initial water level is 40 cm³. After adding the pebble, the water level rises to 57 cm³. What is the volume of the pebble?

36.A person wishes to roast a chicken. The chicken requires 1 hour and 20 minutes in the oven to be properly cooked. The oven must be switched on 10 minutes before any food is put in, in order to pre-heat. The chicken needs to be ready at 4:30 pm. At what time must the oven be switched on?

37.A student measures the time for 20 oscillations of a pendulum as 30.0 s. He then measures the time for 10 oscillations of the same pendulum as 15.2 s. Which measurement gives a more accurate value for the period?

38.A student wants to find the volume of a small, irregularly shaped stone. Which pieces of apparatus should the student use?

39.Which measuring devices are most suitable for determining the length of a swimming pool and the thickness of aluminium foil?

40.A student measures the time for 10 oscillations of a pendulum as 15.2 s. The student's reaction time is 0.25 s. What is the approximate percentage uncertainty in the time for one oscillation?

41.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. What is the independent variable?

42.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Which observation or quantity is the dependent variable?

43.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Which decision best controls another factor in this comparison?

44.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Why should the class repeat measurements or check multiple comparable observations?

45.A class is evaluating an application of measurement, uncertainty and investigations. Which statement identifies a relevant limitation?

46.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Which conclusion is most justified by a controlled comparison?

47.Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Select the two practices that strengthen the validity of this comparison.

48.When evaluating evidence about measurement, uncertainty and investigations, select the two scientifically defensible statements.

49.Design a fair investigation for this question: Compare repeated timings of one pendulum swing with timings of ten swings divided by ten, using a small-amplitude school pendulum. Identify what to compare, what to record and one control.

50.Explain one use of the science in measurement, uncertainty and investigations and evaluate one limitation of the evidence or application.

51.Ten pendulum swings take 18.0 s. If the total timing uncertainty is 0.2 s, what period and corresponding timing uncertainty per swing follow?

52.Two mean results differ by 0.02 s while each has estimated uncertainty 0.05 s. What is the most defensible conclusion?