CHAPTER 1, TEST REVIEW

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1 IB PHYSICS Name: Period: Date: # Marks: XX Raw Score: IB Curve: DEVIL PHYSICS BADDEST CLASS ON CAMPUS 1. Which of the following is equivalent to the joule? A. N m 2 B. N m 2 C. kg m s 2 D. kg m 2 s 2 CHAPTER 1, TEST REVIEW 2. The magnitude of the mass of the universe is of the order of A kg. B kg. C kg. D kg. 3. The current, I, through a resistor is measured with a digital ammeter to be 0.10 A. The uncertainty in the calculated value of I 2 will be A. 1 %. B. 2 %. C. 5 %. D. 20 %. 4. The masses and weights of different objects are independently measured. The graph is a plot of weight versus mass that includes error bars. These experimental results suggest that the A. measurements show a significant systematic error but small random error. B. measurements show a significant random error but small systematic error. C. measurements are precise but not accurate. D. weight of an object is proportional to its mass. Chapter 1 Test Review 1 of 7

2 M 5. The density of a metal cube is given by the expression ρ where M is the mass and V is the volume of V the cube. The percentage uncertainties in M and V are as shown below. M 12 V 4.0 The percentage uncertainty in the calculated value of the density is A B C. 16. D A volume is measured to be 52 mm 3. This volume in m 3 is A m 3. B m 3. C m 3. D m Which of the following is a valid statement? A. A measurement that is not precise can be accurate. B. A measurement that is precise is always accurate. C. A measurement that is not precise will always be inaccurate. D. Repeated measurements will always increase accuracy and precision. 8. The volume V of a cylinder of height h and radius r is given by the expression V = r 2 h. In a particular experiment, r is to be determined from measurements of V and h. The uncertainties in V and in h are as shown below. The approximate uncertainty in r is A. 10. B. 5. C. 4. D. 2. V 7 h 3 Chapter 1 Test Review 2 of 7

3 9. Which of the following lists two scalar quantities? A. emf, momentum B. emf, weight C. impulse, kinetic energy D. magnetic flux, kinetic energy 10. Data analysis question. Gillian carried out an experiment to investigate the craters formed when steel balls are dropped into sand. To try and find the relationship between the diameter of the crater and the energy of impact of steel balls of the same diameter, she dropped a steel ball from different heights h into sand and measured the resulting diameter d of the crater. The data are shown plotted below. (a) (b) (c) The uncertainty in the measurement of d is ±0.40 cm; the uncertainty in h is too small to be shown. Draw error bars for the data point (0.2, 0.047) and the data point (2.0, 0.10). Draw a best-fit line for the data points. The original hypothesis, made by Gillian, was that the diameter of the crater is directly proportional to the energy of impact of the steel balls. Explain why the data does not support this hypothesis. (2) (2) (3) Chapter 1 Test Review 3 of 7

4 (d) Since Gillian s data did not support her hypothesis, she researched to find alternative hypotheses. She found that there are two theories used to predict a relationship between d and h. 1 3 Theory 1 predicts that d = const (h) and theory 2 predicts that d = const (h) 4. In order to test which theory her data supports, she plotted a graph of lg(d) against lg(h). The plot produced a straight line that could be drawn through all the error bars. 1 The graph includes the lines of maximum and minimum gradients based on the first error bar for the first non-zero data point and the last error bar. The last error bar is too small to be shown. State and explain if the original data support theory 1 or theory 2. (4) (Total 11 marks) Chapter 1 Test Review 4 of 7

5 11. Data analysis question. A student performs an experiment with a paper toy that rotates as it falls slowly through the air. After release, the paper toy quickly attains a constant vertical speed as measured over a fixed vertical distance. The aim of the experiment was to find how the terminal speed of the paper toy varies with its weight. The weight of the paper toy was changed by using different numbers of paper sheets in its construction. The graph shows a plot of the terminal speed v of the paper toy (calculated from the raw data) and the number of paper sheets n used to construct the toy. The uncertainty in v for n = 1 is shown by the error bar. Chapter 1 Test Review 5 of 7

6 (a) (b) (c) The fixed distance is 0.75 m and has an absolute uncertainty of 0.01 m. The percentage uncertainty in the time taken to fall through the fixed distance is 5 %. (i) Calculate the absolute uncertainty in the terminal speed of the paper toy for n = 6. (ii) On the graph, draw an error bar on the point corresponding to n = 6. On the graph, draw a line of best-fit for the data points. The student hypothesizes that v is proportional to n. Use the data points for n = 2 and n = 4 from the graph above to show that this hypothesis is incorrect. (3) (1) (1) (3) (d) Another student hypothesized that v might be proportional to n. To verify this hypothesis he plotted a graph of lg v against lg n as shown below. Chapter 1 Test Review 6 of 7

7 Show that the graph verifies the hypothesis that v is proportional to n. (4) (Total 12 marks) Chapter 1 Test Review 7 of 7