Year 9 Science Flashcards
(24 cards)
Identify different energy sources
Renewable: Solar, wind, hydro, geothermal, biomass.
Non-renewable: Coal, oil, natural gas, nuclear.
Define and compare examples of kinetic and potential energy
Kinetic energy is energy of movement (e.g. a moving car, flowing water).
Potential energy is stored energy (e.g. a stretched bow, water at the top of a waterfall).
Describe what is meant by renewable and non-renewable sources of energy and give examples of each
Renewable energy: Can be replenished naturally. is replenished quickly (e.g. solar, wind).
Non-renewable energy: Limited supply. is replenished slowly (e.g. coal, oil).
Describe how a coal-fired power plant works
Coal is burned → heats water → produces steam → spins turbines → drives generators → produces electricity.
Using examples, describe energy transformations and transfers
Example: A toaster transforms electrical energy into heat and light.
Transfer: Energy moves from one object or place to another (e.g. pushing a ball).
Define the term ‘energy’ and identify the unit for energy
Energy: The ability to do work or cause change.
Unit: Joule (J)
Explain efficiency in relation to energy transfers
Efficiency = (Useful energy output ÷ Total energy input) × 100%.
Measures how much input energy is usefully transformed.
Explain how to improve energy efficiency in energy transfers and transformations
Use better insulation, energy-efficient devices, reduce friction, maintain machines.
Construct Sankey diagrams to show energy flow and transformations
Show energy input and how much is useful vs wasted. Width of arrows = amount of energy.
Identify examples of contact and non-contact forces.
Contact: Friction, tension, air resistance.
Non-contact: Gravity, magnetism, electrostatic force.
Identify the elements of a complete circuit .
Conductive path (wires), power source (battery), component (bulb, motor), switch, voltmeter, resistor, ammeter.
Construct circuits and draw circuit diagrams that contain several components to show the flow of electricity through a complete circuit
Use standard symbols for each component. Show all connections in a closed loop.
Describe and apply Ohm’s Law V=I/R
Voltage (V) = Current (I) × Resistance (R).
Use triangle method to rearrange if needed.
Describe what resistance means in a circuit.
Resistance slows down the flow of electric current. Measured in ohms (Ω).
Identify reasons for resistance in a circuit.
Type of material, length of wire, thickness of wire, temperature.
Define the terms ‘pathogen’ and ‘disease’
Pathogen: Microorganism that causes disease.
Disease: Condition that disrupts normal functioning of the body.
Identify examples of pathogens that can cause disease
Bacteria: Tuberculosis
Virus: Influenza
Fungi: Athlete’s foot
Distinguish between infectious and non-infectious diseases
Infectious: Caused by pathogens, spread between organisms (e.g. flu).
Non-infectious: Not caused by pathogens, not contagious (e.g. diabetes).
Give an example of a non-infectious and infectious diseases and their causes
Infectious: COVID-19 (virus).
Non-infectious: Asthma (inflammation of airways).
Provide examples of stimulus-response
Touching a hot surface (stimulus) → Pulling hand away (response).
Bright light (stimulus) → Pupils shrink (response).
Define the term ‘homeostasis’
The process by which the body maintains a stable internal environment.
Describe a condition in the body that should remain stable.
Body temperature (~37°C), blood glucose levels, pH levels, water balance.
What is transformations energy
the process where energy changes from one form to another
what is transfers energy
The movement of energy from one place to another or from one object to another.
