P2 - forces Flashcards
define speed
the speed of an object is the distance travelled in a given amount of time
what are the units for speed?
m/s
when does acceleration occur?
when an object changes velocity
what are the units for acceleration?
m/s^2
what is the gradient of a distance-time graph?
the speed (velocity)
what do flat sections show on a distance-the graph?
where the object has stopped
what does a steeper distance-time graph mean?
the object is going faster
what do curves represent on a distance-time graph?
acceleration
what does a steepening curve mean on a distance-time graph?
the object is speeding up (increasing gradient)
what does a levelling off curve mean on a distance-time graph?
the object is slowing down (decreasing gradient)
what is the gradient of a velocity/speed-time graph?
the acceleration
what do flat sections represent on a velocity-time graph?
steady velocity
what does a steeper velocity-time graph mean?
the steeper the graph, the greater the acceleration or deceleration
what are uphill sections of a velocity-time graph?
acceleration
what are downhill sections of a velocity-time graph?
deceleration
what does a curve mean on a velocity-time graph?
changing acceleration
what is the area underneath the line on a velocity-time graph?
the distance
what are scalars?
scalar quantities have size (magnitude) only
what are vectors?
vector quantities have magnitude and direction
what are some examples of scalars?
distance, speed, mass, temperature etc
what are some examples of vectors?
displacement, velocity, acceleration etc
why is distance a scalar?
distance is how far someone has travelled from a starting point; it has magnitude only so it is a scalar
why is displacement a vector?
displacement is how far in a straight line a person is from that point; it has magnitude and direction so it’s a vector
what is kinetic energy?
the energy an object has when it is moving