Form 4 CHAPTER 1 Measurement........................................ 1 CHAPTER 2 Force and Motion I................................ 8 CHAPTER 3 Gravitation .......................................... 28 CHAPTER 4 Heat .................................................... 41 CHAPTER 5 Waves................................................. 61 CHAPTER 6 Light and Optics.................................. 87 Form 5 CHAPTER 1 Force and Motion II........................... 114 CHAPTER 2 Pressure ........................................... 130 CHAPTER 3 Electricity .......................................... 147 CHAPTER 4 Electromagnetism............................. 164 CHAPTER 5 Electronics ........................................ 180 CHAPTER 6 Nuclear Physics ................................ 196 CHAPTER 7 Quantum Physics.............................. 209 ii CONTENTS Contents GrabMe SPM Physics F4.indd 2 04/11/2022 1:52 PM
CHAPTER 1 MEASUREMENT 1.1 Physical Quantities • Physical quantity is a quantity that can be measured by measuring instruments. Can be measured by metre rule Can be measured by thermometer Can be measured by weighing scale Can be measured by voltmeter Can be measured by ammeter Can be measured by stopwatch Length Temperature Weight Voltage Electric current Time PHYSICAL QUANTITIES • The measurement of a physical quantity is stated in terms of magnitude and unit. Measurement result Physical quantity Magnitude Unit The length of the table is 2.5 m. Length 2.5 m The temperature of the water 50°C. Temperature 50 °C The speed of the car is 80 km h–1. Speed 80 km h–1 Elementary Physics 1 C01 GrabMe SPM Physics F4.indd 1 04/11/2022 2:04 PM
Base Quantities and Derived Quantities • Physical quantities consists of base quantities and derived quantities. • Base quantities are physical quantities that cannot be defined in terms of other quantities. The table below shows seven base quantities and their S.I. unit. Base quantity S.I. unit Quantity Symbol Unit Symbol Length l metre m Mass m kilogram kg Time t second s Temperature T kelvin K Electric current I ampere A Luminous intensity I v candela cd Amount of substance n mole mol 2 C01 GrabMe SPM Physics F4.indd 2 04/11/2022 2:04 PM
Scalar Quantities and Vector Quantities • Scalar quantities are physical quantities that have magnitude only. • Vector quantities are physical quantities that have magnitude and direction. Example Physical quantity Magnitude Direction Scalar / Vector The temperature of water in the glass is 50°C. Temperature ✓ ✗ Scalar The log is pulled by a force of 5 N to the right. Force ✓ ✓ Vector The time taken for the ice to melt is 3 minutes. Time ✓ ✗ Scalar The car is moving with a velocity of 90 km h–1 towards south. Velocity ✓ ✓ Vector • Examples of scalar quantity and vector quantity: Scalar quantities Vector quantities Distance Time Temperature Work Energy Density Speed Volume Power Area Displacement Velocity Force Acceleration Momentum 4 C01 GrabMe SPM Physics F4.indd 4 04/11/2022 2:04 PM
1.2 Scientific Investigation Interpretation of Graphs of Different Shapes Shape of graph Type of graph Interpretation of graph 0 y x A straight line that passes through the origin y is directly proportional to x 2 0 y x A straight line that does not pass through the origin and has positive gradient y increases linearly with x 3 0 y x A straight line that does not pass through the origin and has negative gradient y decreases linearly with x 5 C01 GrabMe SPM Physics F4.indd 5 04/11/2022 2:04 PM
CHAPTER 4 HEAT 4.1 Thermal Equilibrium Two objects A dan B are placed in thermal contact. Heat transfers from A to B and vice versa. B is hotter. Heat transfers from B to A at higher rate. B loses heat and A gains heat. The temperature of B falls while the temperature of A rises. The unbalanced transfer of heat continues until the temperature of A is the same as B. The transfer of heat from A to B equals to the transfer from B to A. The net transfer of heat between A and B is zero. A and B are said to be in thermal equilibrium. Cold Hot Heat transfer B A Heat 41 C04 GrabMe SPM Physics F4.indd 41 25/11/2022 4:32 PM
4.2 Specific Heat Capacity • Heat capacity, C, of an object is the quantity of heat required to raise the temperature of the object by 1°C. C = Q ∆q , Q = quantity of heat supplied Δq = change of temperature Unit for C is J °C–1. • Specific heat capacity, c, of a substance is the amount of heat required to heat up 1 kg of the substance by 1°C. c = Q m∆q , Q = amount of heat (J) m = mass (kg) ∆q = change of temperature (°C or K) Unit for c is J kg–1 °C–1 or J kg–1 K–1. • From the formula c = Q m∆q , the quantity of heat absorbed or released is Q = mc∆q. 42 C04 GrabMe SPM Physics F4.indd 42 25/11/2022 4:32 PM
Example 1 When a stone of mass 0.2 kg is heated with heat energy of 30 J, its temperature is raised by 4°C. Calculate the heat capacity of the stone. Solution Heat supplied, Q = 30 J Change of temperature, Δq = 4°C Heat capacity = Q ∆q = 30 J 4°C = 7.5 J °C–1 Example 2 An electric kettle rated 1 kW is filled with water. Its mass is 1.2 kg dan its temperature is 35°C. When the kettle is switched on for 5 minutes, the temperature rises to 75°C. Determine the heat capacity of the kettle and its content. Solution Heat supplied, Q = Pt = 1 000 W × (5 × 60) s = 300 000 J Change of temperature, Δq = 75°C – 35°C = 40°C Heat capacity = Q ∆q = 300 000 J 40°C = 7 500 J °C–1 43 C04 GrabMe SPM Physics F4.indd 43 25/11/2022 4:32 PM
4.4 Gas Laws Pressure, Temperature and Volume of Gas • Gas consists of very small molecules. • The molecules of gas are always in random motion and collide with the wall of the container. The collision between gas molecules and the wall produces pressure that acts on the wall of the container. • The average kinetic energy of the gas molecules depends on the temperature of the gas. As the temperature of the gas increases, the average kinetic energy of the gas molecules also increases. • Temperature, volume and pressure of the gas based on the Kinetic Theory of Gas: Temperature • The average kinetic energy of the gas molecules increases as the temperature increases. Volume • Gas molecules move freely and fill up the whole space of the container. • The volume of the gas is the same as the volume of the container. Pressure • Gas molecules always move randomly. • When gas molecules collide with the wall of the container, the gas molecules rebound with the change of momentum. The rate of change of momentum exerted force on the wall. • Force per unit area produces gas pressure on the wall of the container. 53 C04 GrabMe SPM Physics F4.indd 53 25/11/2022 4:32 PM
2.1 Pressure in Liquids Tujuan Perniagaan CHAPTER 2 PRESSURE The diagram shows a rectangular block filled with a liquid of density r and a liquid column with height h. Area of the surface A = mn Volume of the liquid column = mnh Mass of the liquid column = volume × density = mnhρ Weight of the liquid column = mass × gravitational acceleration = mnhρg Hence, liquid pressure acting on the surface A = Weight of column Surface area = mnhrg mn = hrg Therefore, it can be concluded that Liquid pressure, P = hrg where h = depth of liquid r = density of liquid g = gravitational acceleration = 9.81 m s–2 The S.I. unit for pressure, P is pascal (Pa) 1 Pa = 1 N m–2 or 1 kg m–1 s–2 A h m n Liquid column Newtonian Mechanics 130 C02 GrabMe SPM Physics F5.indd 130 25/11/2022 4:41 PM
Example 1 A coin is placed in a cylinder filled with water at a depth of 12 cm. Calculate the water pressure acting on the coin. [Density of water = 1 000 kg m–3] Solution Density of water, r = 1 000 kg m–3 Depth of water, h = 12 cm = 0.12 m g = 9.81 m s–2 Water pressure acting on the coin = hrg = 0.12 × 1 000 × 9.81 = 1 177.2 Pa 12 cm Water Coin 10 20 30 40 50 60 70 80 90 100 cc Example 2 A diver dives at a depth of 8.0 m in the sea. Calculate the water pressure acting on the diver. [Density of sea water = 1 100 kg m–3] Water Diver 8.0 m Solution Density of sea water, r = 1 100 kg m–3 Depth of water, h = 8.0 m g = 9.81 m s–2 Water pressure acting on the diver = hrg = 8 × 1 100 × 9.81 = 86 328 Pa 131 C02 GrabMe SPM Physics F5.indd 131 25/11/2022 4:41 PM
Applications of Pressure in Liquids in Our Lives • Position of water tank A water tank in a housing area is built on top of a hill so that the water pressure is higher than the water pressure in the water tank in the house. Water can be transferred easily to the water tank in the house. The water tank in the house is also placed at higher position so that the water pressure in the tank is higher and water can flow out easily through the water pipes. • Position of intravenous liquid A bag of intravenous liquid is hanged at a higher position so that the liquid in the bag can flow easily into the patient’s veins which located at a lower pressure. Water tank Water tank in the house • Use of the siphon Siphon is used to transfer water from a container in higher location to another container at lower location. The flow of water from the end of C produces a region of lower pressure at B. The atmospheric pressure pushes water into the tube at A. B C Siphon A 132 C02 GrabMe SPM Physics F5.indd 132 25/11/2022 4:41 PM
2.3 Gas Pressure Manometer • Manometer is made of a U-tube which contains mercury. It is used to measure gas pressure. Example 5 The diagram shows a manometer connected to a gas supply. 20 cm Mercury Gas A B Metal container Mercury U-tube Calculate the gas pressure in (a) cm Hg dan (b) Pa. [Atmospheric pressure = 76 cm Hg and density of mercury = 1.36 × 104 kg m–3] Solution (a) Pressure at point A = Gas pressure + pressure of mercury column = Gas pressure + 20 cm Hg Pressure at point B = atmospheric pressure = 76 cm Hg Point A and B are at the same level. Hence, pressure at A = pressure at B Gas pressure + 20 cm Hg = 76 cm Hg Gas pressure = 56 cm Hg (b) Applying formula of gas pressure, P = hrg = 0.56 × 1.36 × 104 × 9.81 = 7.47 × 104 Pa 137 C02 GrabMe SPM Physics F5.indd 137 25/11/2022 4:41 PM
3.1 Current and Potential Difference Tujuan Perniagaan CHAPTER 3 ELECTRICITY • There are two types of electric charges: positive charge and negative charge. • Like charges repel each other while unlike charges attract each other. • Quantity of charge is measured in coulomb (C). • Electric field is a region in which a charged particle brought into it will experience an electric force. It is produced surrounding a positive or a negative charge or between two charged particles. • Electric field is represented by arrowed lines which are known as electric field lines. • The characteristics of electric field lines: (a) An electric field line is radially outward from a positive charge and radially in toward a negative charge. (b) Electric field lines do not intersect each other. (c) The density of the electric field lines represents the strength of the electric field. The denser the lines, the stronger the electric field. Electric Field Electricity and Electromagnetism 147 C03 GrabMe SPM Physics F5.indd 147 25/11/2022 4:39 PM
Electric Field Patterns (a) A positively charged particle + (b) A negatively charged particle – (c) Two particles with unlike charges – + (d) Two particles with like charges (+) + + (e) Two particles with like charges (–) – – (f) A charged particle (+) and a charged plane plate (–) + – – – – – – – – (g) A charged particle (–) and a charged plane plate (+) – + + + + + + + + (h) Two parallel plane plates of unlike charges + + + + + + + + – – – – – – – – 148 C03 GrabMe SPM Physics F5.indd 148 25/11/2022 4:39 PM
Electric Field Strength • The electric field strength, E, is defined as the electric force acting on a unit of positive charge placed in the electric field. Electric field strength, E = F q where F = electric force (unit: N) q = quantity of electric charge (unit: C) • For two parallel charged plates, the electric field strength is calculated by the following formula. Electric field strength, E = V d where V = potential difference between the two plates d = distance between the two plates (in metre) Example 1 The diagram shows two parallel plates at a distance of 10 cm is connected to a voltage of 500 V. Calculate the electric field strength between the two plates. Solution Potential difference, V = 500 V Distance, d = 10 cm = 0.1 m Electric field strength, E = V d = 500 0.1 = 5 000 V m–1 + + 10 cm 500 V + + + + + + – – – – – – – – 149 C03 GrabMe SPM Physics F5.indd 149 25/11/2022 4:39 PM
Electric Current • An electron, e, carries a negative charge of 1.6 × 10–19 C. • The flow of charges (electron) through a conductor produces electric current. • Electric current is the rate of flow of charge in a conductor. Current, I = Q t where Q = quantity of charge t = time taken S.I. unit for current: A (ampere) Example 2 A battery is connected to a bulb. 2 C of electric charges flow through the bulb in 5 s. Calculate the current flowing through the bulb. Solution Quantity of charge, Q = 2 C Time, t = 5 s Current, I = 2 5 = 0.4 A Example 3 The current that flows through a resistor is 1.5 A. Calculate the quantity of charge that flow through the resistor in 1 minute. Solution Current, I = 1.5 A Time, t = 1 min = 60 s From I = Q t , Q = It = 1.5 × 60 = 90 C 150 C03 GrabMe SPM Physics F5.indd 150 25/11/2022 4:39 PM
Potential Difference • The potential difference between two points in an electric circuit is the work done (or energy transferred) to drive one coulomb of charge through the two points. Potential difference, V = W Q or V = E Q where W = work done E = energy transferred S.I. unit for potential difference: V (volt) Example 4 In an electric circuit, 480 J of work is done to drive 40 C of electric charges through an electric bulb. Calculate the potential difference across the bulb. Solution Work done, W = 480 J Quantity of charge, Q = 40 C V = W Q = 480 40 = 12 V Example 5 150 J of energy is used to drive electric charges through a resistor. Calculate the quantity of charges transferred if the potential difference across the resistor is 6 V. Solution Energy, E = 150 J; Potential difference, V = 6 V Q = E V = 150 6 = 25 C 151 C03 GrabMe SPM Physics F5.indd 151 25/11/2022 4:39 PM
5.1 Electron Tujuan Perniagaan CHAPTER 5 ELECTRONICS • Factors affecting the rate of thermionic emission: Surface area of the metal The bigger the surface area, the higher the rate of emission. Temperature of the metal The higher the temperature, the higher the rate of emission. Type of metal The rate of emission depends on the type of metal. For example, magnesium has a higher rate of emission than iron. Type of coating Rate of emission increases when the metal is coated with metal oxide. Cathode Rays The electron beam moving from cathode to anode in a vacuum tube at high velocity is known as cathode rays. Thermionic Emission Thermionic emission is the emission of electrons from the surface of a heated metal. Applied Physics 180 C05 GrabMe SPM Physics F5.indd 180 25/11/2022 4:37 PM
• A transistor is made by coalescing the n-type semiconductor and p-type semiconductor and has three terminals, which are emitter, E, base, B and collector, C. Terminal Function Emitter, E Supplies charge carriers to the collector Base, B Controls the flow of charge carriers from the emitter to the collector Collector, C Receives charge carriers from the emitter • There are two types of transistor: npn transistor pnp transistor Structure Symbol Structure Symbol Collector (C) Emitter (E) N N Base (B) P C E B Direction of current: B → E Collector (C) Emitter (E) P P Base (B) N C E B Direction of current: E → B 5.3 Transistor 189 C05 GrabMe SPM Physics F5.indd 189 25/11/2022 4:37 PM