Physics 0625/62 May/June 2020: question paper and mark scheme

Question

A student investigates the period of a pendulum. Fig. 1.1 and Fig. 1.2 show the apparatus she uses. clamp clamp d bob one complete oscillation Fig. 1.1 Fig. 1.2 (a) Explain briefly, with the help of a diagram, how you would use a metre rule and set square to measure the length d of a pendulum as accurately as possible. Diagram: …… [3] (b) The student adjusts the pendulum so that d = 50.0 cm. She displaces the bob slightly and releases it so that it swings. Fig. 1.2 shows one complete oscillation of the pendulum. She measures the time t1 for 20 complete oscillations. (i) Record the time t1 shown in Fig. 1.3. 1 m s 100 s Fig. 1.3 t1 = …… [1] (ii) Calculate the period T1 of the pendulum. The period is the time for one complete oscillation. T1 = …… [1] (c) The student adjusts the pendulum until the distance d is 100.0 cm. She repeats the procedure and records the time t2 for 20 oscillations and the period T2. 39.80 s t2 = …… 1.99 s T2 = …… She measures the mass mA of the pendulum bob. The reading on the balance is shown in Fig. 1.4. bob g Fig. 1.4 Record mass mA of the pendulum bob to the nearest gram. mA = …… g [1] The student repeats the procedure using a pendulum bob of mass mB. 109 g mB = …… She obtains these results: 50.0 cm distance d = …… 1.39 s period T3 = …… 100.0 cm distance d = …… 2.02 s period T4 = …… (d) (i) Using the results T1, T2, T3 and T4, for the period of each of the pendulums, tick (3) the response that matches your results within the limits of experimental accuracy. the period T is affected by d only the period T is affected by both d and m the period T is affected by m only the period T is not affected by d or m [1] (ii) Justify your answer to (d)(i) by reference to the results. …… [1] (e) The student now investigates the effect of the size of the oscillations on the period of the pendulum. (i) Suggest briefly how you would measure the size of an oscillation. You may draw a diagram. …… [2] (ii) State one variable that you would keep constant during this part of the investigation. …… [1] [Total: 11]

Question

A student determines the resistance of a resistance wire. Fig. 2.1 shows the circuit he uses. power supply A l resistance wire B sliding contact C V Fig. 2.1 (a) • The student places the sliding contact C on the resistance wire at a distance l = 10.0 cm from B. • Record, in the first row of Table 2.1, the potential difference V across the length l = 10.0 cm of resistance wire, as shown on the voltmeter in Fig. 2.2. 1 2 0.4 0.6 0.2 0.8 0 3 0 1.0 V A Fig. 2.2 Fig. 2.3 • Record, in the first row of Table 2.1, the current I in the circuit as shown in Fig. 2.3. • Complete the column headings in Table 2.1. Table 2.1 l/ V/ I/ 10.0 30.0 0.7 0.30 50.0 1.1 0.27 70.0 1.5 0.28 90.0 2.1 0.29 [3] (b) The student repeats the procedure using l = 30.0 cm, 50.0 cm, 70.0 cm and 90.0 cm. The readings are shown in Table 2.1. Plot a graph of V / V (y-axis) against l / cm (x-axis). Start both axes at the origin (0,0). [4] (c) (i) Write a conclusion about the value of the current I in the circuit as the position of the sliding contact C is changed. …… [1] (ii) Justify your conclusion by reference to your results. …… [1] (d) Using the graph, determine the potential difference VL when the length l = 60.0 cm. Show clearly on the graph how you obtained your result. VL = …… [2] [Total: 11]

Question

A student investigates some thermal properties of sand and water. Fig. 3.1 shows the apparatus. thermometer beaker bench Fig. 3.1 (a) The thermometer in Fig. 3.2 shows the room temperature θS at the beginning of the experiment. Record θS. –10 0 10 20 30 40 50 60 70 80 90 100 110 °C Fig. 3.2 θS = …… °C [1] (b) The student is supplied with hot water at a temperature θH. She records the temperature of the hot water. 84 °C θH = …… She pours 100 cm3 of hot water into a beaker that contains sand. Initially, the sand is at room temperature. She measures the highest temperature θM of the mixture. 70 °C θM = …… (i) Calculate the rise in temperature θR of the sand using the equation θR = (θM – θS). θR = …… °C [1] (ii) Explain briefly what the student does after pouring the hot water into the sand and before taking the temperature, in order to obtain a reliable value for θM. …… [1] (iii) Calculate the fall in temperature θF of the hot water using the equation θF = (θH – θM). θF = …… °C θ Calculate the ratio S using the equation S = R . Give your answer to a suitable number of significant figures for this experiment. θF S = …… [1] (c) The student pours 100 cm3 of the hot water into a clean beaker that contains 100 cm3 of water at room temperature. She records the highest temperature θM of the mixture. 49° C θM = …… Calculate the rise in temperature θR of the cold water using the equation θR = (θM – θS). Use the value of room temperature θS recorded in (a). θR = …… Calculate the fall in temperature θF of the hot water using the equation θF = (θH – θM). θF = …… θR Calculate the ratio W using the equation W = . θF W = …… [2] (d) The student studies the thermal properties of sand and water. She predicts that S should be equal to 6 × W. State whether the results support the prediction. Justify your answer by reference to the readings. statement …… justification …… [2] (e) Suggest two temperatures that it would be sensible to keep constant when carrying out the experiments. 1. …… 2. …… [2] (f) The student measures the volume of the dry sand using a measuring cylinder before carrying out the experiment. Tick (3) the boxes that show the precautions that she should take in order to obtain an accurate reading. Take the reading at the bottom of the meniscus. Tap the measuring cylinder to make sure the top of the sand is horizontal. View the scale of the measuring cylinder at right angles. [1] [Total: 11]

Question

A student investigates the bending of 1 m length strips of different materials. She compares how far they bend when loaded at one end. Plan an experiment to investigate how the material from which the strips are made affects the bending of the strips when loaded at one end. The following apparatus is available to the student: strips of wood, plastic, steel and aluminium, each of length 1 m a set of slotted masses a metre rule a G-clamp (used to hold the strips to the laboratory bench). Other apparatus normally available in a school laboratory can also be used. In your plan, you should: • draw a diagram to show the arrangement of the apparatus • explain briefly how you would carry out the investigation, including the measurements you would take • state the key variables to be kept constant • draw a suitable table, with column headings, to show how you would display your readings (you are not required to enter any readings in the table) • explain how you would use the results to reach a conclusion. …… [7] [Total: 7]