PHYSICS PAPER 1 DEFINITIONS

resultant vector

the single vectore which has the same effect as the original vectors acting together

weight

the gravitational force the earth exerts on any object on or near its surface

normal force

the perpendicular force exerted by a surface on an object in contact with it

frictional force

the force that opposes the motion of an object

newtons first

an object continues in a state of rest or uniform (moving with constant) velocity unless it is acted upon by a net or resultant force

newtons second

when a net force, Fnet, is applied to an object of mass, m, it accelerates in the direction of the net force

newtons third

when object A exerts a force on object B, object B simultaneously exerts am oppositely directed force of equal magnitude on object A

inertia

the property of an object that causes it to resist a change in its state of rest of uniform motion

current

the rate of flow of charge

potential difference

the work done per unit positive charge

resistance

a material's opposition to the flow of electric current

ohms law

the current through a conductor is directly proportional to the potential difference across the conductor at constant temperature

EMF

the total energy supplied per coulomb of charge by the cell

newtons law of universal gravitation

every particle with mass in the universe attracts every other particle with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres

gravitational filed

a region in space where a mass will experience a force

electric field at a point

the force per unit positive charge

coulombs law

two point charges exert forces on each other. the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between the charges

vector

a physical quantity that has both magnitude and direction

scalar

a physical quantity that has magnitude only

distance

the length of path travelled

displacement

a change in position

speed

the rate of change of distance

velocity

the rate of change of displacement

acceleration

the rate of change of velocity