1. Motion Flashcards
What is distance?
Distance is a scalar quantity which specifies how far two points are apart.
What is displacement?
Displacement is a vector quantity which specifies distance and direction.
The gradient of a distance time graph is the
The gradient of a distance time graph is the speed.
The gradient of a displacement time graph is the
The gradient of a displacement time graph is the velocity.
The gradient of a speed time graph or a velocity time graph is the
The gradient of a speed time graph or a velocity time graph is the acceleration.
The area under a speed time graph is the
The area under a speed time graph is the distance travelled.
The area under a velocity time graph is the
The area under a velocity time graph is the displacement.
‘The area under a graph’ is…
‘The area under a graph’ is the area between the graph and the time axis.
Average speed =
Distance / time
Average velocity =
Displacement / time
Define acceleration.
Acceleration is the rate of change of velocity with time.
a =
v - u / t
v =
u + at
Average speed =
2nd equation
v + u / 2
A scalar quantity is one with …
Size only
A vector quantity is one with …
Both size and direction
Define speed
Distance travelled in unit time
Define velocity
Distance travelled in unit time in a specified direction
Is speed a scalar or vector quantity?
Scalar
Is velocity a scalar or vector quantity?
Vector
When the velocity of a body increases or decreases, we say that it …
Accelerates
Is acceleration a scalar or vector quantity?
Vector
Which axes do distance and time go onto on a distance/time graph?
Distance - y axis
Time - x axis
A horizontal line on a distance-time graph means that the body is …
Stationary
S =
1/2 (u + v) t
v2 =
u2 + 2as
When working out average speed from a distance-time graph, we do not work it out for each section and then take an average, but instead we work it out for the ….
entire journey in one fell swoop
S =
Second equation
ut + 1/2 at2
When doing questions involving motion, always choose a direction to call ….
Positive
Give an example of the force of friction
Air resistance or drag
If a car moves at a steady speed, the forward force from the engine must be …
balanced by an equal backwards force, called air resistance (a force of friction).
The total stopping distance of a car is made up of what two parts?
The thinking distance and the braking distance.
Total stopping distance =
Thinking distance + braking distance
When an object moves through a fluid (liquid or gas) the opposing frictional forces are called …
Drag
Drag depends on the … of the object moving through the fluid.
shape
To know when a driver applies the brakes, look at when the velocity begins to …
Decrease
