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Question 1

what is power

Answer 1

the rate at which energy is transferred
measured in watts

power=work done/time taken

Question 2

what is a force field

Answer 2

the space around an object where it can affect other objects

Question 3

why is a contact force

Answer 3

objects interact by exerting forces on each other. if the the forces are touching then the forces between them are contact forces

Question 4

what is gravity

Answer 4

a force that occurs between any two objects that have mass

Question 5

what is a magnetic field

Answer 5

the space around a magnet where it can affect other materials

Question 6

what is an electric field

Answer 6

an object charged with static electric
he electric field can affect objects around it.
two objects with the same charge that are close with each other a pair of forces that are equal in size acting in opposite directions.

Question 7

what is an a amperes

Answer 7

what electric current is measured in. often shortened to amps.it uses an metre that that is connected to a series to mesquite the current passing through it.

Question 8

what are the 2 different types of current

Answer 8

There are two types of
current direct and alternating. In a direct current, the flow of electrons is consistently in one direction around the circuit, in an alternating current, the direction of electron flow continually reverses.

Question 9

what is a moment

Answer 9

A turning effect of a force. is the turning effect of a force. Moments act about a point in a clockwise or anticlockwise direction. The point chosen could be any point on the object, but the pivot. - also known as the fulcrum - Is usually chosen.
measured in newton meters

Question 10

want is potential difference

Answer 10

Potential difference (or voltage) is a measure of energy, per unit of charge, transferred between two points in a circuit. A potential difference of 1 volt means that 1 joule of work is done per coulomb of charge.
the bigger the potential difference across the component the bigger the current

Question 11

what is electric current measured in

Answer 11

coulombs. one coulomb is the charge that passes a point in a circuit when there is a current of 1 amp for 1 second

Question 12

what is a magnetic material

Answer 12

one that is naturally attracted to magnets and can become a magnet

Question 13

how do you make a temporary magnet

Answer 13

you have too bring a magnetic material to a magnet as long as there together its a temporary magnet

Question 14

what are the two types of current

Answer 14

Direct current (DC) – when the electrons flow in one direction around a circuit.
Alternating current (AC) – when the direction of the electron flow continually reverses.

Question 15

how is current measured

Answer 15

in amps using an ammeter

Question 16

what is an electric current

Answer 16

An electric current is a flow of charged particles. In metal conductors the charged particles are free electrons. The electrons are free to move from one ion to another and a net flow of these electrons in one direction is an electric current.

Question 17

how to measure the size of electrical current

Answer 17

amount of charge that passes a point per second.

equation charge=current x time

charge is measured in colons

U=I x T

Question 18

what is the equation for potential difference

Answer 18

current x resistance

v=I x r

Question 19

what is a series circuit

Answer 19

1.in a series circuit the same current flows through all the different electrical components so the current and all parts of the circuit are the same
2.the total potentiel différence is shared between all the electrical components
the total resistance of all components in a series circuit is the sum of the resistance of each component

Question 20

what is the equation to work out the total resistance of multiple components in a Series cell circuit

Answer 20

resistance total = the sum of all the individual resistances added together

Question 21

what its static electricity

Answer 21

Electric charge that accumulates on an insulated object, for example because of friction.

Question 22

what does a van de Graf generator do

Answer 22

A Van de Graaff generator removes electrons to produce a positive charge. A person does not have to touch the Van de Graaff generator to start feeling the effects, as static electricity is a non-contact force . This force will act on any charged particle in the electric field around the generator.

A person touching the dome of the Van de Graaff generator will also lose electrons and become positively charged. The same will happen to each of their hairs. Since the person, their head, and each of the hair follicles are all positively charged, the hairs will repel from the head and from every other strand causing them to stick out from the head in all directions.

Question 23

what is shown on an electric field diagram

Answer 23

Fields are usually shown as diagrams with arrows:
The direction of the arrow shows the way a positive charge will be pushed.
The closer together the lines are, the stronger the field and the greater the force experienced by charges in that field. This means that the field is stronger closer to the object.

Question 24

what would DC look like on a voltage time graph and what provides DC

Answer 24

On a voltage-time graph this would appear as a straight horizontal line at a constant voltage.
Car batteries, dry cells and solar cells all provide a direct current (dc) that only flows in one direction.

Question 25

how do plugs work

Answer 25

A plug connects a device to the mains electricity supply. The cable between the device and the three-pin plug contains three copper wires that are coated with plastic.

Question 26

what is a fuse

Answer 26

A fuse provides a built-in fail-safe to the electrical circuit for a device. The fuse contains a thin wire that will melt if the current gets too high. If there is a fault that causes the casing of the device to become live, a large current will flow through the live wire and low-resistance earth wire. This high current will cause the fuse to melt.
Once the fuse has melted, the circuit is broken and no more current flows through the device.

Question 27

what is a permanent magnet

Answer 27

A permanent magnet is often made from a magnetic material such as iron. A permanent magnet always causes a force on other magnets or magnetic materials. Key features of a permanent magnet:
it produces its own magnetic field
the magnetic field cannot be turned on and off – it is there all the time
Bar magnets and horseshoe magnets are examples of permanent magnets.

Question 28

how can a magnetic field be discovered

Answer 28

A magnetic field is invisible, but it can be detected using a magnetic compass. A compass contains a small bar magnet on a pivot so that it can rotate. The compass needle points in the direction of the Earth’s magnetic field, or the magnetic field of a magnet.