forces - an introduction Flashcards
what is a scalar
magnitude (size) only
eg. distance, temperate, time and mass
what is a vector
magnitude and direction
eg. velocity shoes the speed and direction of travel
what do arrows represent
vector quantities
the length of the arrow - magnitude
arrow points in the direction that the vector is acting
what is a force
vector quantity, a push or pull that acts on an object due to an interaction with another object.
force is measure in Newton
what is a contact force
two objects that are physically touching
eg. friction, tension, air resistance
what is a non- contact force
objects that aren’t touching
eg. gravitational, electrostatic, magnetic
what is gravity
a force of attraction between all masses
what does mass tell us
-the amount of matter the object contains
-measured in Kg
-scalar quantity
what is weight
the force acting on an object due to gravity
the weight is directly proportional to the mass
what is the equation for weight
weight(N) = mass(kg) x gravitational field strength(N/kg)
what is the centre of mass
the weight of an object can be considered to act at a single point
what is the gravitational field strength on the earth
10N/kg
what is the resultant force
single force that has the same effect as all the original forced acting together
how do you work out resultant force
subtract the smaller force from the larger force
