SPM Science 2017, Paper 2 (Question 1 & 2)

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Question 1:
Diagram 1 shows an experiment to study the transmission of pressure in liquid by hydraulic system. A weight is added on the big piston’s syringe. The suitable weights are added on the small piston’s syringe until both pistons are at the same level. The weight added represents the force acting on both pistons.

Diagram 1

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The result of the experiment is shown in Table 1.

Table 1

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(a) Based on the result in Table 1, draw a graph to show the force acting on the small piston against the force acting on the big piston on the graph paper provided. [2 marks]



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(b) Based on the graph in 1(a), what is the force acting on the small piston if the force acting on the big piston is 8 N? [1 mark]

(c) What is the factor being fixed in this experiment? [1 mark]

(d) Name an appliance that uses the same principle as in Diagram 1. [1 mark]

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Answer:
(a)


(b) 3.2 N (± 0.1)

(c) Volume of water

(d) Hydraulic brake / Hydraulic jack



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Question 2:
Diagram 2 shows an experiment to study the effect of light on the growth of bacteria.
Diagram 2

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The condition of the nutrient broth in test tube P and Q is observed after three days.
The result of this experiment is recorded in Table 2.

Table 2

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(a) State one observation on the nutrient broth which has been kept in the black box for three days. [1 mark]

(b) State one inference for this experiment. [1 mark]

(c) State the variables in this experiment. [2 marks]
(i) Manipulated variable
(ii) Responding variable

(d) Based on this experiment, state the operational definition of bacteria. [1 mark]

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Answer:
(a) Condition of nutrient broth is cloudy.

(b) The bacteria grow actively in dark condition.

(c)(i) Presence of light

(c)(ii) Condition of nutrient broth

(d) Bacteria is a microorganism that caused the condition of nutrient broth turns cloudy.

Derive By First Principle – Example 1

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Solving Equation of Index Number

Example

Derive the equation $$y = {x^2} + \frac{3}{x}$$ by using first principle.

$$\eqalign{ & y = {x^2} + \frac{3}{x} \cr & \frac{{dy}}{{dx}} = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\delta y}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\left( {y + \delta y} \right) – y}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\left[ {{{\left( {x + \delta x} \right)}^2} + \frac{3}{{x + \delta x}}} \right] – \left[ {{x^2} + \frac{3}{x}} \right]}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{{x^2} + 2x\delta x + \delta {x^2} – {x^2} + \frac{3}{{x + \delta x}} – \frac{3}{x}}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} \frac{{2x\delta x + \delta {x^2}}}{{\delta x}} + \frac{{\frac{{3x – 3(x + \delta x)}}{{x(x + \delta x)}}}}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} 2x + \delta x + \frac{{ -3 \delta x}}{{x(x + \delta x)}} \times \frac{1}{{\delta x}} \cr & = \mathop {\lim }\limits_{\delta x \to 0} 2x + \delta x + \frac{{ – 3}}{{x(x + \delta x)}} \cr & = 2x – \frac{3}{{{x^2}}} \cr} $$

$$\frac{{dy}}{{dx}} = \mathop {\lim }\limits_{\delta x \to 0} \frac{{\delta y}}{{\delta x}}$$

Selesaikan Persamaan Nombor Indeks – Contoh 1

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Selesaikan Persamaan Nombor Indeks

Contoh

Selesaikan persamaan 5x-1 + 5x+2 = 3150

$$\eqalign{
& {5^{x – 1}} + {5^{x + 2}} = 3150 \cr
& \frac{{{5^x}}}{5} + {5^x} \times {5^2} = 3150 \cr
& \frac{{{5^x}}}{5} + \frac{{125 \times {5^x}}}{5} = 3150 \cr
& 126 \times {5^x} = 5 \times 3150 \cr
& {5^x} = \frac{{5 \times 3150}}{{126}} \cr
& {5^x} = 125 = {5^3} \cr
& x = 3 \cr} $$

$$\eqalign{
& {a^m} \times {a^n} = {a^{m + n}} \cr
& {a^m} \div {a^n} = \frac{{{a^m}}}{{{a^n}}} = {a^{m – n}} \cr
& {\text{Hence}} \cr
& {5^{x – 1}} = {5^x} \div 5 = \frac{{{5^x}}}{5} \cr
& {5^{x + 2}} = {5^x} \times {5^2} \cr} $$

Solving Equation of Index Number – Example 1

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Solving Equation of Index Number

Example

Solve the equation 5x-1 + 5x+2 = 3150

$$\eqalign{
& {5^{x – 1}} + {5^{x + 2}} = 3150 \cr
& \frac{{{5^x}}}{5} + {5^x} \times {5^2} = 3150 \cr
& \frac{{{5^x}}}{5} + \frac{{125 \times {5^x}}}{5} = 3150 \cr
& 126 \times {5^x} = 5 \times 3150 \cr
& {5^x} = \frac{{5 \times 3150}}{{126}} \cr
& {5^x} = 125 = {5^3} \cr
& x = 3 \cr} $$

$$\eqalign{
& {a^m} \times {a^n} = {a^{m + n}} \cr
& {a^m} \div {a^n} = \frac{{{a^m}}}{{{a^n}}} = {a^{m – n}} \cr
& {\text{Hence}} \cr
& {5^{x – 1}} = {5^x} \div 5 = \frac{{{5^x}}}{5} \cr
& {5^{x + 2}} = {5^x} \times {5^2} \cr} $$

Derived Quantities

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1.2.2 Derived Quantities

  1. A derived quantity is a Physics quantity that is not a base quantity. It is the quantities which derived from the base quantities through multiplying and/or dividing them.
  2. For example, speed is define as rate of change of distance, Mathematically, we write this as Speed = Distance/Time. Both distance and time are base quantities, whereas speed is a derived quantity as it is derived from distance and time through division. Example
    (Speed is derived from dividing distance by time.)
  3. Belows are the derived quantities that you need to know in SPM. You need to know the equation of all the quantities, so that you can derive their unit from the equation.
  4. If you find it difficult to memorise all these equation, you can skip it now because you are going to learn all of them in the other chapter. 

Base Quantities

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1.2.1 Base Quantities

Physical Quantity

  1. A physical quantity is a quantity that can be measured.
  2. A physical quantity can be divided into base quantity and derived quantity.

Base Quantities

  1. Base quantities are the quantities that cannot be defined in term of other physical quantity.
  2. The base quantities and its units are as in the table below:
TIPS: In SPM, you MUST remember all 5 base quantities and its SI unit.

Introduction to Physics

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Introduction to Physics

1.1.1 Understanding Physics

Physics is a branch of science that studies the

  1. natural phenomena
  2. properties of matter
  3. energy

Field of study in Physics

The field of studies in Physics including

  1. Motion
  2. Pressure
  3. Heat
  4. Light
  5. Waves
  6. Electricity
  7. Magnetism and electromagnetism
  8. Electronics
  9. Nuclear Physics

8.5.1 Alloy (Structured Questions)

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Question 1:
Figure 1.1 shows the formation of bronze.


(a) On figure 1.1, name the atoms of metals, P and Q. [2 marks]

(b) Name process W. [1 mark]

(c)(i) State one property of bronze. [1 mark]
 
(ii) State the effect of the atoms of metal Q in bronze. [1 mark]

(d) The medal in Figure 1.2 is made of bronze.
Give one property of the medal if it is made of metal P only. [1 mark]


Answer:
(a) 
P: Copper
Q: Tin

(b)
Alloying

(c)(i) Harder/ can withstand corrosion better than copper.

(c)(ii) The atoms of metal Q in bronze prevent the layers of atoms of metal W in the bronze from sliding easily over one another.

(d) Softer, more malleable, less resistant to corrosion. 


Question 2:
Diagram 2.1 shows an experiment to study the resistance of steel alloy towards corrosion.



After 3 days, the result obtained is shown in Diagram 2.2.



(a) Based on Diagram 2.2, write down one observation for this experiment. [1 mark]

(b) Write down one hypothesis for this experiment. [1 mark]

(c) State the variables in this experiment.
(i) Constant variable [1 mark]
(ii) Manipulated variable [1 mark]

(d) Predict the condition of the steel nail on the 5th day. [1 mark]

(e) Based on this experiment, state the operational definition for an alloy. [1 mark]


Answer:
(a) The iron nail has corroded while the steel nail has not.

(b) Steel is more resistant to corrosion than iron.

(c)(i) Distilled water, number of days the nails are immersed in water.
(any one)

(c)(ii) Type of metal (steel on iron)

(d) The steel nail will remain not corroded

(e) An alloy is a mixture of metal which is harder and more resistant to corrosion than a pure metal.

8.4.1 Radio Communication (Structured Questions)

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Question 1:
Diagram 1.1 shows three types of electronic components used in a radio receiver.

Diagram 1.1

(a) Name electronic components W and Y. [2 marks]

(b) State the function of electronic component X. [1 mark]


(c) Diagram 1.2 shows a black diagram of a radio receiver.

Diagram 1.2

(i) Write any two electronic components, W, X or Y from Diagram 1.1 into the corresponding blocks provided in Diagram 1.2. [2 marks]

(ii) What type of wave is received by T?
Mark (\/) your answer in the box provided in Diagram 1.3. [1 mark]

Diagram 1.3

Answer:
(a)
W: Diode
Y: Transistor

(b)
  1. Stores electric charges and discharges them at regular intervals when required
  2. To channel the flow of radio frequency carrier waves into the Earth.
  3. When connected in parallel with the inductor, it determines the frequency of the radio wave that will be detected.

(any one)



(c)(i)

(c)(ii)



Question 2:
Table 1 shows the symbols of electronic components.
(a) Complete Table 1 using the name of electronic components given. [3 marks]


Table 1

Diagram 2 shows a block diagram of a radio receiver system.
(b) What is the function of P? [1 mark]

(c) What is Q? [1 mark]

(d) State the energy change that occurs at Q? [1 mark]


Answer:
(a)


(b) Receives modulated radio waves from stations.

(c)(i) Loudspeaker

(c)(ii) Electrical energy → sound energy