Shared Flashcard Set

Details

Y7 Definitions
Compact, precise ways of explaining a physics term for Y7 pupils
27
Physics
Not Applicable
07/26/2005

Additional Physics Flashcards

 


 

Cards

Term
Definition of a force.
Definition
A Push or a pull

OR

That which changes or tend to chage the state of rest or motion of a body.

OR

That which produces acceleration or deformation in a body.

Measured in newton (N).

Term
Definition of a vector quantity.
Definition
A quantity that has direction as well as magnitude (or size!)
Term
Definition of a scalar quantity.
Definition
A quantity that has only size associated with it.
Term
Definition of mass
Definition
The quantity of matter that a body contains. This is the same wherever the body is and is measured in kilogrammes (kg).
Term
Definition of weight.
Definition
The force with which the mass of a body is pulled by gravity. This changes depending upon where the body is placed within a gravitational field.

It is a force so weight is measured in newtons (N).

Term
Definition of matter.
Definition
Matter is anything which occupies space.

There are four forms of matter - plasma (which you won't come across until you are older)

- gas

- liquid

- solid

The three common forms of matter are made up of atoms.

Term
Definition of gravitational field strength.
Definition
GFS tells you with what force a 1kg mass would be pulled if it were placed in that field of gravity.

On Earth each kilogram is pulled by gravity towards the centre of the Earth with a pull of 10N, so the g.f.s. of Earth is 10N/kg

Term
State the Law of Conservation of Energy
Definition
Energy is neither created nor destroyed, it merely changes from one form to another
Term
What is kinetic energy?
Definition
Movement energy - a body only possesses it if it is moving.

The faster it moves the more kinetic energy it has.

Term
What is gravitational potential energy?
Definition
Energy due to the position of the body in the gravitational field.

The further away the object is from the centre of the Earth the greater the GPE is.

Term
What is elastic energy?
Definition
It is a form of potential energy due to the stored energy from a stretched or squashed piece of material.

If a body would spring into a different shape or position when released it has some stored (or potential) elastic energy in it.

Term
What types of energy usually accompany a change into kinetic energy?
Definition
Sound (any movement sets up vibrations) and

heat (movement usually results in friction which produces a change into heat energy)

Term
What type of energy change usually accompanies a change into electrical energy
Definition
Heat (wires always get hotter ehen a current passes through them).
Term
What is a transfer of electrical energy?
Definition
Electrical energy transfer is via an electrical current passing across a potential difference (a voltage).

The bigger the current the bigger the transfer of electrical energy

The bigger the potential difference the bigger the transfer of electrical energy and

the longer the current flows the bigger the transfer of electrical energy.

Term
What is necessary in a circuit for a current to flow?
Definition
There must be a power supply to provide the potential difference (either a mains run lab pack or a battery) and a complete circuit of conductor for the current to run through (no gaps or insulators in the pathway!)
Term
What is a conductor?
Definition
A material that allows electrical charge to pass through it.
Term
Name a good conductor.
Definition
Metals are good conductors. Copper is very good, but not as good as silver or gold!
Term
What is an electrical insulator?
Definition
A material that does not allow charge to pass through it easily. Gases are good insulators (that is why an air gap in a circuit stops the currrent flowing!) and so are plastics.
Term
What moves when a current passes through a wire?
Definition
The electrons or the atoms that make up the wire.
Term
State Hooke's Law
Definition
The extension of a spring (how much bigger it gets!) is directly proportional to the load applied (force with which it is pulled) as long as the elastic limit has not been exceeded.

(If you stretch it past the elastic limit it will not return to its original size and its properties have been altered).

Term
What is potential difference?
Definition
Voltage

It is potential difference that provides a kind of 'electrical slope' for the electrons to 'slide down'. Without a potential difference no current will flow - the bigger the potential difference the faster the electrons move and the larger the current flow.

Term
What is electrical current?
Definition
A flow of charge. In a wire it is the movement of electrons (which have negative charge) that make up the current.

Never say the current is 'fast' or 'slow' - it is always big or small. It is the charge movement that is fast or slow!
Term
Which is correct: There was 6V of potential difference through the lamp

or

There was 6V of potential difference across the lamp?

Definition
There was 6V of potential difference across the lamp?

NEVER say voltage 'through' anything.... it is always across!

Term
What is a fuse?
Definition
A fuse is a piece of wire that only allows a current up to the value stamped on it to flow through it. If the current exceeds that value the fuse-wire gets too hot and melts. This makes a gap in the circuit and the current can no longer flow.
Term
What is a short circuit?

[image]
Definition
This occurs when a wire is connected across a component giving the current the chance to go through it rather than the component.

The component then is by-passed and usually does not get enough voltage across it to make it function. If it is a lamp it just goes out.

[image]

Term
What is a parallel circuit?
Definition
A circuit where the components are connected as shown in the diagram below:

[image]

Each component has its own link to the power supply without having to go through the others. Each component gets the full voltage from the power supply.

Term
What is a series circuit?
Definition
A circuit where the components are connected as shown in the diagram below:

[image]

There is no separate route to the power supply for each component - they are joined and share out the voltage.

Supporting users have an ad free experience!