paper 2 Flashcards
what is a vector
has magnitude and direction
what is a scalar
just a magnitude
what are vectors represented by
arrows and their length determine the vectors magnitude
what is a force
a push or pull acting on an object due to interaction with other objects
what is a non contact force
it is when the 2 objects do not have to be touching
2 types are electrostatic and gravitational attraction
what is a contact force
this is when the objects are physically touching
such as a normal contact force and friction
what is weight
the force exerted on mass by a gravitational field
what happens to a persons mass and weight when they are on different planets
their mass stays the same but their weight is different as a result of planets having different gravitational field strengths
what is the gravitational field strength of earth
9.8
where is the weight of an object considered to act
at the objects centre of mass
what is the resultant force
single force representing the sum of all forces acting on an objects
what is terminal velocity
this is when all the forces acting on an object are equal resulting in the object moving at a constant speed
what is work done
Work done is when energy is transferred from the object doing the work to another form
Work done against frictional forces causes a rise in temperature of the object
what is required to bend stretch or compress an object
To stretch, bend or compress an object, more than one force has to be applied
If a single force is applied to an object, it will just move in that direction
elastic deformation
The object returns to its original shape when the load has been removed
plastic deformation
The object does not return to its original shape when the load has been removed
what is hookes law
The extension of an elastic object, such as a spring, is directly proportional to the force applied
what is displacement
it is a vector that includes both distance and direction
what is velocity
speed in a given direction
it is also a vector
what happens to the velocity of an object if it is consistently moving in a circle
the velocity constantly changes
and a change in velocity is acceleration meaning that although it may not be speeding up it is accelerating as it is constantly changing direction
displacement time graphs
Gradient is velocity
Sharper gradient means faster speed
Negative gradient is returning back to starting point
Horizontal line means stationary
Curved Line means that the velocity is changing
(acceleration)
If an object is accelerating, its speed can be
determined by drawing a tangent
velocity time graphs
Gradient is acceleration
Sharper gradient means greater acceleration
Negative gradient is deceleration
Horizontal line means constant speed
0 Velocity means that it is stationary
Area under line = distance traveled
Curved Line means that the acceleration is changing
Newtons first law
An object has a constant velocity unless acted on by a resultant force
Newtons second law
The acceleration of an object is proportional to the resultant force acting on the object, and
inversely proportional to the mass of the object.
