Physics Paper 2 Topic 5- Forces pg Topic 6 Waves pg Topic 7 magnetism and electromagnetism

Transcription

1 9-1 GCSE Combined Science Knowledge Organiser Physics Paper 2 Topic 5- Forces pg Topic 6 Waves pg Topic 7 magnetism and electromagnetism

2 Physics Revision 5) Forces Contact/non-contact; Mass/weight (pg 76/77) Vector and scalar quantities: A vector has.and Some examples of vector quantities are:. Vectors are represented by., the length of the arrow tells us the..of the quantity. Label the velocities of the motorbikes: A scalar only has. Some examples of scalar quantities are:. Mass and Weight: Mass is the amount of... in an object. The mass stays the. anywhere in the universe. It is measured in.. Weight is a.. acting on an object due to g. The weight of an object. with its location. It is measured in. You can think of the weight acting at a single point called the c..of m Label it on this object: Contact and non-contact forces: Forces are and They are caused by things i.. with each other. Sometimes two objects have to touch for the force to act the force is a.... Force. When two objects don t have to touch for the force to act the force is a.. Force KEY WORDS: Vector Scalar Contact Non-contact Interaction Mass Weight Gravitational field strength Centre of mass Mass and Weight are proportional: Weight = mass x G...F...S... ( ) ( ) (N/kg) W = m x g m = g = Value of g on Earth is...n/kg Value of g on the moon is...n/kg

3 Physics Revision 5) Forces Resultant Forces (p78/79) What is the definition of a resultant force? Draw a free body diagram of a car: Work Done: When a resultant force an object, is done. Work done = E.T. Write the equation for work done - In words: In symbols: Fill in the triangle: Calculate the resultant force: Scale diagrams: Draw all the forces acting t. to t.. Draw a straight line from start of.. force to.... of the last force. Choose a s..s.(e.g. 1cm:1N) 3N Keywords: Resultant Force Free body diagram Work done Scale diagram 4N Use this diagram to explain how to find the resultant force

4 Physics Revision 5) Forces Equilibrium and Components (p80) Equilibrium/balanced forces: An object is in equilibrium if Components: You can split a force into components if it acts at an a... angle. Its easier if the two components are at r... a... to each other. Acting t...these components have the same effect as the single force. Summarise the four steps for drawing components: Draw the triangle of forces to show that they have no resultant force: Explain how you would find the missing force on an object if you are told that it is in equilibrium: Remember the forces arrows join t... to t Keywords: Equilibrium scale diagram resultant force components Horizontal vertical tip-to-tail

5 Physics Revision 5) Forces Elasticity (p82-85) Deformation: Three ways of transferring energy are s..., c... or b... All of these can happen when you apply a...on an object. When a pair of forces stretches or compresses an object we say that w... i... d... Equation for Springs: Extension is directly proportional to the force applied. Write the equation: When work is done on an object in this way its p... e... store increases. Extension, e means... Elastic deformation is Spring constant, k means Inelastic deformation is Limit of proportionality: Explain the shape of the graph what is the significance of the point marked P? Keywords: Stretch compress bend applied force Work done elastic deformation inelastic deformation Proportional extension spring constant Limit of proportionality Area under straight line = E.. S.=

6 Physics Revision 5) Forces Distance/Displacement/Speed/Velocity/Acceleration (p87/88) Distance/Displacement: Explain the difference between speed and displacement: Acceleration: Acceleration is the c in v in a certain amount of t... The equation is: a = Δv t Explain each symbol a Δv t What does deceleration mean?... Speed/velocity: Speed and Velocity both measure Uniform acceleration: Uniform acceleration means Equation is: Speed is a s.. quantity Velocity is a v.quantity Equation: Give the equation and units for each quantity Typical speeds: Person Walking Running- Cycling- Transport Car- Train- Plane- KEYWORDS: Distance Displacement Speed Velocity Acceleration Deceleration Uniform

7 Physics Revision 5) Forces Distance/time graphs and Velocity/time graphs pages 89/90 Distance/Time graph - describe what is happening in the graph at the points: A: Match the graph to the description of motion: B: C: D: What does the gradient tell us?.... Velocity/Time graph label the diagram: The area under the graph tells us The gradient tells us KEY WORDS: Distance Gradient Speed Velocity Acceleration Velocity-time graphs Now work out the acceleration and distance moved in each case

8 Physics Revision 5) Forces Drag and Terminal Velocity (p91/92) Drag: Friction will cause objects to speed up/ stay the same/ slow down. Friction acts between two.in contact. Friction always acts in the same/opposite direction to movement. Drag is the resistance you get in a f.. Fluids are l. and g.. Air resistance is a type of drag - what produces it?... How can we reduce drag? Terminal Velocity: 1) When falling objects first.., the force of gravity is than the slowing them down, so they accelerate. 2) As the.. The friction builds up. 3) This gradually the. Until eventually the. Is equal to the.. (so the r f is zero). 4) It will have reached its maximum speed or t. v... and will fall at a steady speed. Explain how terminal velocity depend on shape and area: What happens to drag when speed increases? Keywords: Drag friction Air Resistance Streamlined Fluid Resultant force Acceleration Terminal velocity Surface area

9 Physics Revision 5) Forces Newton s Laws and Inertia (p94/95) 1 st Law: State Newton s first law in words. Acceleration can have 5 different forms: Using the formula F=ma, fill in the table a b c d e Force (Newtons, N) Mass (kilograms, kg) Acceleration (meters/second squared, m/s 2 ) Inertia: Explain what inertia is.. 2 nd Law: When we have unbalance forced on an object there is a r..f Newton s second law say that a is proportional to the resultant force. 3 rd Law: When t..o..interact, the forces they exert on each other are e and o. Give an example of an interaction pair: Write the equation that describes the law: (Say what each symbol means and give units) Keywords: Resultant force Stationary Acceleration Inertia Interaction pair

10 Physics Revision 5) Forces Stopping Distances/Reaction times (p99/100) Stopping Distance: What is stopping distance, and what are the two parts that make up a car s stopping distance? Reaction Times: What is a reaction time? What factors affect stopping distance? Describe the steps of an experiment that could test a person s reaction time. T D is affected by: B D is affected by: S Distance = T. Distance + B.. Distance Keywords: Stopping Distance Thinking Distance Braking Distance Speed Reaction Time

11 Physics Revision 5) Forces Braking Distances and Momentum (p101/102) Braking Distances: Summarise the points about braking distances from the revision guide: 1. What is momentum? What are the units for this equation: p = m X v momentum ( / ) = mass ( ) X velocity ( / ) Complete the question below using the equation above. If a sprinter with a mass of 50kg runs at a velocity of 10m/s what is their momentum? A 0.5 kg trolley is pushed at a velocity of 1.2 m/s into a stationary trolley with a mass of 1.5 kg. The two trolleys stick to each other after the impact. Calculate: - The momentum of the 0.5 kg trolley before the collision. -The velocity of the two trolleys straight after the impact. 4. What is conservation of momentum and how do you calculate it? KEY WORDS: Braking Distance Mass Velocity Momentum Conservation of momentum

12 Displacement Physics Revision Topic 6) Waves p105 Wave Basics In what direction do waves transfer energy? Key Definitions Amplitude is... Wavelength is... Distance Label this wave with the amplitude, wave length, rest position, crest and trough. When waves travel through a medium: What oscillates? What is transferred? What stays in the same place overall? Give an example of this. Frequency is... Period is... It is measured in... The formula to find the period of a wave is = What is the period of a wave if the frequency is 10Hz? KEY WORDS: Energy transfer Oscillation Amplitude Wavelength Frequency Period

13 Physics Revision Topic 6) Waves p106 Transverse and Longitudinal Transverse Waves have... Longitudinal Waves have... The are perpendicular to the of energy. The oscillations are to the direction of transfer. Add arrows to show the direction the wave is travelling and the directions of the vibrations. Give examples of transverse waves: Add arrows to show the direction the wave is travelling and the directions of the vibrations. Then label the compressions and rarefactions. Give examples of longitudinal waves: Wavespeed is... Complete the wave equation: Wave Speed = x = Example: A microwave has a frequency of 5.2 x 10 8 Hz. Find its wavelength. ( The speed of microwaves in 3.0 x 10 8 m/s.) KEY WORDS: Transverse Longitudinal Perpendicular Parallel Vibrations Energy Transfer Wavespeed Frequency Wavelength Compressions Rarefactions

14 Physics Revision Topic 6) Waves p Experiments with Waves Measuring the Speed of Water Ripples Measuring the Speed of Waves on Strings 1: What will you do? What will happen? 2: What will you adjust? When do you stop? 2 whole wavelengths = 0.84m 1: What will you do? What will you see? 2: What will you do? Why does this happen? 3: Why is the strobe suitable? 4: What will you measure? How do you find the average wavelength? 5: What equation will you use? Note: we simply took a photograph of the waves to freeze them. 3: What will you measure? 4: How do you know the frequency? 5: How can you find the speed of the wave? Example: if the frequency needed to get the wave in the picture was 12Hz, what is wavespeed? KEY WORDS: Frequency Wavelength Wavespeed Ripple Tank Strobe light Signal Generator

15 Physics Revision Topic 6) Waves p Refraction When a wave arrives at a boundary between two materials, it can be A, T or R. If Absorbed energy is often transferred to... If Transmitted often leads to.... Refraction: when... The wavefronts here are closer together this shows... Ray Diagrams Explaining refraction Read points 1-7 on p109: a)what happens when a wave crosses a boundary? b)if a wave slows down, which way does it bend? c)if a wave speeds up, which way does it bend? d)what does how much it speeds up depend on? e)what happens to the wavelength and frequency in refraction? When the wave hits the boundary not face on, the wave... When a wave crosses a at an, only of a wavefront crosses the boundary at first. That part travels than the rest of the. The faster part of the wave front travels than the part. This causes it to. (p110) Label the incoming ray, boundary, angle of incidence, normal, angle of refraction and refracted ray. Here, the angle of is smaller than the angle of. This tells us the second material is... A wavefront is... KEY WORDS: Absorbed Transmitted Reflected Medium Density Wavefronts Normal Refraction Incidence

16 Physics Revision Topic 6) Waves p112 Electromagnetic Waves Electromagnetic Waves make up a Spectrum: Properties of EM Waves delete as appropriate All EM Waves are transverse/longitudinal. They transfer matter/energy from a source to an absorber. They all travel at different/the same speed through a vacuum (3.0x10 8 m/s). The eye can detect some/all of the EM Spectrum. EM waves have different/same frequency. EM waves are generated/changed by changes in atoms and their nuclei. EM waves are used for different purposes because of their different names/properties. Making Radio Waves with Oscillating Charges Radio waves an produced using an current. The radio waves have the same as the current that caused them. How do we know that electromagnetic waves can travel through a vacuum? KEY WORDS: Electromgnetic Continuous Spectrum Transverse Wavelength Frequency Absorbed Vacuum Vibrations Receiver Nucleus Properties Gamma X-Ray Ultraviolet Infrared Visible Microwave Radio

17 Physics Revision Topic 6) Waves p Uses of EM Waves Radio waves (p113) What is each type of EM Wave used for? Uses of Microwaves (p113-4) Complete the diagram to show how TVs and mobiles work. Microwaves (p113-4) Infrared (p114) Visible Light (p115) Ultraviolet (p115) In cooking, microwaves are absorbed by molecules, which... X-rays (p115) Gamma rays (p115) Uses of X-Rays and Gamma Rays in Medicine (p115) What can X-rays pass through easily? What can t they pass through so easily? Uses of Radio Waves (p113) Long wavelengths can further around the surface of the earth, so can be received even if the isn t in the line of sight of the t. What do radiographers use X-rays and gamma rays for? Why are gamma sources suitable as tracers? Uses of Infrared (IR) (p114) all objects emit IRpppp The colours on an infrared camera image tell us... Absorbing IR causes objects... Explain how an X-ray image is formed.

18 Physics Revision Topic 6) Waves p116 Dangers of Electromagnetic Waves The effects of each type of EM Radiation are based on... What are the hazards associated with each type of radiation? EM wave Dangers Low frequency waves... Radio What is Radiation Dose measured in? What is Radiation Dose? UV X-Ray Gamma but high frequency waves... What 2 things does the risk depend on? What must be considered before EM Radiation is used? Which 3 types are ionising radiation? What could be a hazard of visible light? What could be a hazard of Infrared Radiation (which we feel as heat)? For example, why would a person in a car accident be given an X-ray scan, when X- rays can cause cancer? Look at the radiation dose chart on the left. What does the m stand for in msv? How many Chest X-rays would a person have to have before there was any statistical risk of cancer? KEY WORDS: Hazard Risk Gamma X-Ray Ultraviolet Infrared Visible Light Microwaves Radiowaves Frequency Energy Ionising Sievert (Sv) Dose Exposure

19 Physics Revision Topic 6) Waves p117-8 Infrared Radiation and Temperature All objects and Infrared Radiation (IR). The hotter an object is... Required Practical: The Leslie Cube (p118) Objects at constant temperature... Type of Surface Dark, matt White or shiny Emitting Absorbing What might the four surfaces on a Leslie Cube be? What is poured into the Leslie Cube? What is the Independent Variable (that we change)? Leslie Cube Emission Investigation (p118) In this space, sketch a bar graph predicting the results of the experiment. Why should we do the experiment more than once? What is the Dependent Variable (that we measure)? What are our Control Variables (that we keep the same to ensure a fair test)? KEY WORDS: Leslie Cube Absorption Emission Surface Thermometer Independent Dependent Control Temperature Repeatable Infrared Radiation Celsius Variables Bar Graph

20 GCSE 9-1 Physics Revision paper 2 7) Magnetism- magnets pg Magnets pg 122 match sentence starts/ends All magnets produce a magnetic field which the further apart the lines are drawn Moving charge and magnetic field Pg 123 Explain the diagram The closer together the lines are The weaker the magnetic field The lines always go from The magnetic force is always strongest Two unlike poles will north to south can be shown by drawing field lines the stronger the magnetic field attract each other at the poles How can you tell the difference between a magnet and a magnetic material? Electromagnet pg 124 1) What is a solenoid? 2) How do you turn a solenoid into an electromagnet? Magnetic field pg 122 Draw a magnetic field around a magnet. Label the poles, show what a compass will look like as it is positioned around the magnet 3) What is the advantage of an electromagnet over a permanent magnet? 4) State two ways of making an electromagnet even stronger 5) State three uses of electromagnets

21 GCSE 9-1 Physics Revision paper 2 7) Magnetism- motors pg The motor effect pg 126 Colour code key: The wire : Flemings left hand rule pg 127 Calculating the size of the force pg 127 State what each symbol represents and the units The magnetic field due to the current in the wire F= B I l The magnetic field of the permanent magnet Explain what is happening in this diagram (pg 126) The combined magnetic effect The force of the motor effect order statement The continual making and breaking of the contacts allows the motor to continue spinning. 1 When the switch is closed, the current flows and the coiled wire becomes an electromagnet. When it reaches the vertical position, the momentum of the spinning allows the brushes to make contact again, so the electromagnet is switched back on The electromagnet coil is repelled by the permanent magnet, so it starts to spin As it spins, the circuit is broken so the electromagnet is temporarily turned off Label Permanent magnet Electromagnet coil Where the circuit connects to the electromagnet Where the circuit breaks its connection to the electromagnet