Exam🥲 Flashcards
Identify some common mixtures
Sand and water.
Salt and water.
Sugar and salt.
Identify the solute and solvent in common mixtures.
Solute: substance that is dissolved in a solution is called a solute. Solvent: you dissolve a solute in here to create a solution.
whats filtering?
the process in which solid particles in a liquid or gaseous fluid are removed by the use of a filter
whats sieving
The process of separating fine particles from the larger particles by using a sieve
whats decanting
the process of pouring away a liquid while leaving a solid
distillation
heating a liquid to the boiling point
evaporation
water changes into a gas or water vapor
crystallization
when a chemical it converted from a liquid into a solid crystalline state.
Chromatography
separating a mixture of chemical substances into its individual components
How is salt separated from seawater from desalination plants
reverse osmosis technology to separate water molecules from seawater.
Identify solar and lunar eclipse
Solar is when the moon is in the middle and lunar is when earth is in the middle.
What is mass, weight, and unit of force?
Mass is the amount of matter in an object and weight is a force due to gravity pull. Weight is measured in Newton’s coz it’s a force. unit of force is n.
What’s renewable and non renewable?
Renewable is something that can be used repeatedly and does not run out because it’s naturally replaced. Non renewable is when something will run out or will not be replenished for thousands or even millions of years.
What’s speed multiplying machines and force multiplying machines?
Speed multipliers are devices that increase the speed of, or distance travelled by, an object and force multipliers are devices that increase the force of and object.
How can a mechanical advantage be obtained from simple machines?
Multiply the idea mechanical advantage of the simple machine
Distinguish between simple and compound machines
Simple machines are levers, pulleys, wheel and axles, wedge, screws and inclined planes. Compound machines are two of these together
Identify how simple machines work together in compound machines
Simple machines are attached together to make compound machines, for example a crane.. if there was no pulley, it would just be a lever moving up and down. That doesn’t make life easy.
Explain the seasons in terms of the tilt of the earths axis and the orbit of the earth around the sun.
when the North Pole tilts toward the Sun, it’s summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it’s winter in the Northern Hemisphere.
Describe the developments of models of the universe and solar system put forward by astronomers.
Firstly, Plato discovered that the planets followed perfectly circular motions around the sun. Then Heraclides decided to make a model of it by placing the planets in the correct order from the earth. They called it the geocentric solar system model.
Explain why the amount of daylight varies from season to season and distance from the equator.
because the hemisphere is tilted away from the sun, it wouldn’t get as much light as the hemisphere that’s directly getting the sunlight. This brings warmer weathers meaning different seasons.
How to reduce friction.
Machines and engines use grease and oil to reduce friction so they can last longer.
