Linear motion
What is the equation for acceleration?
Force = mass x acceleration OR Acceleration = force / mass
What are the 5 key descriptors important in linear motion?
- Distance - Displacement - Speed - Velocity - Acceleration/deceleration
What are three types of graphs used in linear motion?
- Distance/time - Speed/time - Velocity/time
What are the important things for graphs of linear motion?
- Plot time on the horizontal axis / x axis - Label the axes, including units in brackets - Use a curved line of best fit
How is linear motion achieved?
From a direct force being applied to a body, where the force is applied directly to the centre of a body's mass
How is gradient calculated?
Gradient = change in y axis / change in x axis
How is speed calculated?
Speed = distance / time taken
How do you use a distance/time graph to calculate speed?
Speed = distance/time
What is Newton's first law of motion?
A body continues in a state of rest or uniform (constant) velocity unless acted upon by an external or unbalanced force
What is direct force?
A force applied through the centre of mass resulting in linear motion
What is a distance/time graph?
A visual representation of the distance travelled plotted against the time taken
What is a speed/time graph?
A visual representation of the speed of motion plotted against the time taken
What is a velocity/time graph?
A visual representation of the velocity of motion plotted against the time taken
Give an example of linear motion
A water skier on a flat lake being pulled at constant speed will travel in linear motion as all parts of the body will travel in the same direction over the same distance per unit of time
How do you use a velocity/time graph to calculate acceleration?
Acceleration = (final velocity - initial velocity) / time
How is acceleration calculated?
Acceleration = (final velocity - initial velocity) / time taken
How is deceleration calculated?
Deceleration = (final velocity - initial velocity) / time taken Deceleration measures how quickly someone is slowing down
How do you use a speed/time graph to calculate distance travelled?
Distance travelled can be measured ; as the area under the speed/time curve is equal to the distance travelled by a body
When using the equation F=MxA, explain the result if it were positive, negative or zero
If the result is; Positive -> acceleration is occurring Negative -> deceleration is occurring Zero -> no acceleration and the body is either at rest or travelling at constant velocity
What is linear motion?
Movement of a body in a straight or curved line, where all parts move the same distance, in the same direction over the same time
What is Centre of mass?
The point at which a body is balanced in all directions. The point from which weight appears to act.
What is deceleration?
The rate of change (decrease or negative) in velocity (m/s/s or m/s2)
What is velocity?
The rate of change in displacement (m/s) (in a direction)
What is speed?
The rate of change in distance (m/s)
What is acceleration?
The rate of change in velocity (m/s/s or m/s2)
What is displacement?
The shortest straight-line route from start to finish positions, measured in metres
What is the gradient?
The slope of a graph at a particular moment in time
What is biomechanics?
The study of human movement and the effect of force motion on sports performance
What is distance?
The total length covered from the start to finish positions, measured in metres
What is common about displacement, velocity and acceleration?
They are measures of size and direction, which gives a more precise picture of motion
What is common about measures of distance and speed?
They only measure size
How is velocity calculated?
Velocity = displacement / time taken
