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| Question | Answer |
| Why does a metal expand when heated? | The particles move further away from each other by other particles vibrating and hitting each other |
| What is the equation for pressure in solids? | Pressure=Force/Area |
| What is the equation for pressure in liquids? | Force=Gravitational pull X Density X Depth |
| Would there be more pressure exerted on a smaller facet or a larger facet and why? | Smaller facet as more pressure is pushed on a smaller surface area however on a bigger facet, the concentration of the pressure extends and the force would be less spread out. |
| What is a pascal (Pa)? | A pascal is 1N/cm sq or 10,000N/m sq |
| Why does a wide puddle evaporate more quickly than a deep puddle? | This is because more particles are at the surface of the water and due to this more get pushed out at the same time |
| Which would evaporate quicker and why? A) A puddle on a hot day B) A puddle on a cold day | A because on a hot day the particles move quicker and vibrate more and push each other quicker whereas on a normal day, the particles go at a slow constant pace. |
| What is the difference between boiling and evaporating? | Boiling is a very quick process and can only happen at a certain temperature whereas evaporation is a very slow process and can happen at many different temperatures. |
| Do molecules vibrate quicker in hotter or colder metals and why? | In a hotter metal because the molecules are hitting each other quicker. |
| How does heat transfer with conduction? | Heat transfers from a higher temperature to a lower temperature |
| Why are solids better heat conductors than liquids and liquids than gases? | Solids have a stronger bond and liquids and gases have weaker bonds |
| Why does hot air rise and why doesn't cold air rise? | It is less dense than cold because it has less particles per unit of volume. |
| How does heat transfer? | Heat transfers without movement or presence of particles/matter. |
| What is thermal energy transferred by? | Thermal energy is transferred by light (Electromagnetic waves) called infrared. |
| What does a vacuum flask do? | It stops heat transfers from higher to lower temperatures. |
| How does a vacuum flask stop heat transfers? | The insulators reduce heat loss by conduction. The vacuum by convection and conduction. Shiny glass reflects IR light and reduces heat losses by radiation. The bung stops heat escape by convection |
| How do you stop heat loss in a home (5 methods)? | Use double glazed windows Use cavity wall insulation Use fibreglass on the loft Use carpets on the floor Use a draught excluder by convection |
| Can energy be created? | Energy can't be created or destroyed, but can only be transferred. |
| What is the unit for energy and what does it stand for? | J and this stands for joules |
| What is the formula to find out the efficiency? | Useful energy / Input energy X 100 |
| Does the sun rise in the east or the west? | The east and it sets in the west |
| Is the sun higher in the summer or the winter and why? | It is higher in the summer because the sun takes longer to set. |
| Why is it hotter in the summer? | This is because the sun is out longer and more heat is produced. This is because it is more concentrated on one area. |
| What does it mean if a hemisphere is tilted towards the sun? | It is summer and if it is tilted away then it is winter. |
| Name all the equinoxes and solstices | Spring equinox- Around 21st March Autumn equinox- Around 23rd September Summer solstice- Around 21st June Winter solstice- 22nd December |
| What is an equinox and what is a solstice? | Equinox- When day and night are the same length Solstice- The longest or shortest day of the year |
| What is the approximate tilt of the earth? | 23.5 degrees |
| What is a solar eclipse? | When the moon comes between the earth and the sun blocking out the sun's rays. |
| What is a lunar eclipse? | When the moon moves into the umbra of the earth's shadow, so it can't be seen |
| What are stars used for? | Navigation Farming Astrology |
| What are light years? | A unit of measurement used to determine how far stars and planets are away from each other |
| What is a constellation? | Patterns of stars in the sky |
| What is a comet? | A ball of dust and ice normally orbiting the sun, far beyond any planets. |
| What is a moment? | A turning effect of a force |
| What is the formula for moments? | M= F X D Moment= Force X Perpendicular Distance |
| What happens at equilibrium? | The sum of the anti clockwise moments are equal to the clockwise moments. |
| What is the centre of mass of an object? | A point where all the weight acts through |
| Is it better if the centre of mass is lower or higher? | It is better if it is lower |
| How do you make an object more stable? | You put weights at the bottom, you widen the base or you make the object smaller in height and lower the centre of mass. |
| What is stable equilibrium? | When the weight falls within the base. |
| What are machines? | They make jobs easier |
| How do machines work? | They make the load closer to the pivot and therefore, when you apply a force further away from the load, less effort is needed. |
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