SIJIL PELAJARAN MALAYSIA 2006 PHYSICS PAPER 3
Section A Answer all questions 1.
A student carries out an experiment to investigate the relationship between the length of air column, l, and the temperature, θ, for a fixed mass of air. The air is trapped by concentrated sulphuric acid in a capillary tube. Diagram 1.1 shows the thermometer and capillary tube tied on a metre rule. The sealed end of the capillary tube is placed at the zero mark on the scale of the ruler.
The thermometer and capillary tube are placed into a beaker filled with water. The arrangement of the apparatus is shown in Diagram 1.2.
Ice cubes are put into the beaker until the temperature, θ, reaches 0 ºC. The actual reading of the length of the air column, l, is shown in Diagram 1.4 on page 10. Then the beaker is heated until the temperature, θ, reaches 20 ºC. The actual corresponding reading of the length of the air column, l, is shown in Diagram 1.5 on page 10. The procedure of the heating process is repeated with temperature, θ = 30 ºC, 40 ºC, 50 ºC, 60 ºC and 70 ºC. The actual corresponding reading of the length of the lengths of the air column, l, are shown in Diagrams 1.6, 1.7, 1.8, 1.9, and 1.10 on pages 10 and 11.
(a) For the experiment described on pages 5 and 7, identify: (i) The manipulated variable Temperature / θ (ii) The responding variable Length / l (b) (i) Diagram 1.3 shows the meniscus of the concentrated sulphuric acid inside the capillary tube.
State the correct position of the eye while taking the reading of the length of the air column. Top section of meniscus
(ii) Based on Diagrams 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 and 1.10 on pages 10 and 11, determine the lengths of air column, l, and their corresponding temperatures, θ. Tabulate your results for θ and l in the space below. Θ / ºC
l / cm
0 20 30 40 50 60 70
7.1 7.6 7.9 8.1 8.4 8.7 9.0
(c) On the graph paper on page 15, plot a graph of l against θ. (d) Based on your graph, state the relationship between l and θ. l increases linearly with θ. (e) State one precaution that should be taken to obtain the accurate readings of l. The capillary tube and ruler scale must be parallel. Trapped air column must always be below the water level / immersed.
1 (c)
2
A student carries out an experiment to investigate the relationship between the potential difference, V, across a filament bulb and the current, I, flowing through it. The results of the experiment is shown in the graph of V against I as in Diagram 2.1 on page 19. (a) Based on the graph in Diagram 2.1, determine the value of V when I = 0.2A. Show on the graph, how you determine the value of V. V = 2.92 V ± 0.02 (b) Ohm’s Law states that the potential difference across a conductor is directly proportional to the current flowing through the conductor. Based on the statement above, determine the range of the current that obeys the Ohm’s Law. Show on the graph how you determine the range of the current. 0.0 A – 0.12 A (c) The gradient of the graph represents resistance. State how resistance varies with current. When I increases resistance increases. (d) The electric power, P, used by the bulb is given by the formula P = I2 m, where m is the gradient of the graph. (i) Calculate the gradient, m, when I = 0.2 A. Show on the graph how you determine m. m
= = =
3 0 3 0 22
. . . .
84 − − 24 84 17 .6 Ω
0 . 00 0 . 07
(ii) Calculate The value of P when the current I = 0.2 A.
P = I
2
R
= ( 0 . 2 ) 2 ( 22 . 6 ) = 0 . 904 W
(d) State one precaution that should be taken to improve the results of this experiment. -
Ensure all connections in the circuit are tight No leakage of current / short circuit ( any relevant response )
Kertas 3 – Bahagian B • Konstruk yang diuji – Penyelesaian Masalah secara Saintifik – 12 markah
Inference: Hypothesis: Aim:
[RV] depends on [MV] As [MV] increases, [RV] will increase To investigate the relationship between [MV] and [RV]
Variables a) Manipulated variable – b) Responding variable – c) Fixed variable – [Labelled diagram]
Procedure: 1. Set up of the apparatus 2. First value of the manipulated variable 3. Show how the responding variable is determined 4. Show repetition using another four values of manipulated variable.
• Tabulate the result of the experiment using at least two columns • State the graph plotted – RV against MV
Section B Answer any one question. 3 Diagram 3.1 shows two wooden tops. One of the tops is partly coated with tin. Both tops are the same size and are rotated with the same velocity. Diagram 3.2 shows the top which is partly coated with tin able to spin longer
Based on the above information and observation: (a) State one suitable inference. (b)
State one suitable hypothesis.
(c)
With the use of apparatus such as a hacksaw blade, plasticine and other apparatus, describe an experiment framework to investigate the hypothesis stated in 3(b). In your description, state clearly the following: (i)
Aim of the experiment.
(ii) Variables in the experiment. (iii) List of apparatus and materials. (iv) Arrangement of the apparatus. (v) The procedure of the experiment which include the method of controlling the manipulated variable and the method of measuring the responding variable. (vi) The way you would tabulate the data. (vii) The way you would analyse the data.
3 (a) Time for the body to stop spinning depends on mass (b) As mass increase, the time for the body to spin increase. (c) (i) To investigate the relationship between mass and period. (ii) Manipulated variable : mass Responding variable : period Fixed variable : Length of hacksaw blade / number of oscillations (iii) Mass balance, stop watch, plasticine, G-clamp // Figure (iv) The hacksaw blade is clamped at one end horizontally // Figure (v) -
Plasticine with the mass ,m, 50g is attached to the other end of the hacksaw blade. The blade is displaced downward and released. The time taken for 10 complete oscillations is taken using stop watch, t. The period of oscillation is calculated, T = t/10 Repeat the previous steps using plasticine of mass, m = 100g, 150g, 200g and 250g.
(vi)
(vii)
Mass, m/g
Period, T/s
Period, T(s)
Mass, m(g)
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