Forces and Motion Flashcards
Accelerate
To change speed
Air resistance
A force that slows things down when moving through air. It is caused by friction and by the object pushing the air out of its way.
Balanced forces
When two forces on an object are the same strength, but in opposite directions
Drag
Another name for air/water resistance
Fluid
A gas or liquid
Friction
A force between two objects that are touching. It usually acts to slow things down or prevent movement.
Resultant force
The difference between forces in two opposite directions.
Unbalanced forces
When two forces in opposite directions are not the same strength
Upthrust
A force that pushes things up
Water resistance
A force that slows things down that are moving through water. It is caused by friction and by the object pushing the water out of the way
Weight
The amount of force with which gravity pulls something towards the earth. It is measured in newtons (N)
Chemical energy
Energy that is stored in chemicals eg. Fuel, batteries and food.
Deform
Change shape
Dissipate
Spread out
Efficiency
How much energy something wastes
Elastic potential energy
Energy stored in stretched or squished things that can change back to their original shape. Otherwise known as strain energy.
Electricity
A way of transferring energy through wires
Gravitational potential energy
Energy stored in objects in high places that can fall down.
Kinetic energy
A name used to describe energy when it is stored in moving things
Law of conservation of energy
The idea that energy can never be created or destroyed, only transferred from one store to another.
Light
Transferring energy by waves. Light waves can travel through transparent materials and through empty space.
Nuclear energy
Energy stored in materials
Solar energy
Energy from the sun
Thermal energy
Energy stored in hot objects.
Mean speed
Total distance / time taken = mean speed
Distance time graph
Shows how far/fast something travels on a journey
Steeper the lines means faster traveled
Relative speed
The speed of one object compared to another - both could be moving
Distance multiplier
A lever or other machine where the load moves further than the effort
Effort
The force used eg. Force used when pulling the load
Load
The weight or force in something. For a machine, the load is the weight that is being moved.
Fulcrum
A point on which something turns. Another name for a pivot.
Moment
That turning effect of a force.
Force X Distance from the force to the pivot
Work
The energy transferred when a force moves an object.
Work = force x distance moved in the direction of the force
