Show Menu

NCEA level 1 mechanics summary sheet with definitions, example questions, etc.

Speed, Distance, Time

measured in metres per second, ms-1
measured in metres, m
measured in seconds, s, a measure of how long something takes
distance = velocity x time
Distance Time Graphs
-line upward­s=g­etting farther away
-line downwa­rds­=ge­tting closer
-flat line=s­taying still


force = mass x accele­ration
-weight is a force measured in Newtons which changes depending on where you are eg. Earth vs. Mars
-mass is the amount of matter contained in an object measured in kilograms.
Effect of doubling the mass or force
-if you double the mass but keep the force the same, accele­ration will be halved
-if you double the force, accele­ration will be doubled


the measure of energy transfer when an object is moved over a distance
Work (J) = Force (N) x Distance (m)
When work is done to an object, the object gains energy
When an object does work, it loses energy
work done=e­nergy lost or gained
The Ramp Question
If one ball is thrown up a ramp and the other is dragged up, both balls will gain the same amount of gravit­ational potential energy assuming they are lifted to the same height, so the work done will be equal, assuming no energy is lost as heat and sound.


a measure of how fast your speed is increa­sing, symbol is 'a', measured in ms-2
a measure of how fast your speed is decreasing
Speed Time Graphs
-line upward­s=c­onstant accele­ration
-line downwa­rds­=co­nstant decele­ration
-flat line=c­onstant speed
-area under the graph=­dis­tance travelled

Friction and Pressure

friction is caused when things rub against each other
-friction transfers kinetic energy into heat and sound energy
-friction increases when rougher or larger surfaces contact
-friction ALWAYS opposes motion
-it is measured in Newtons, N
Air Resistance is a form of friction affecting all objects moving through the air
Terminal Velocity occurs when forces become equal and opposite so they are their constant, maximum speed
Eg. when a parachute opens the force of air resistance increases because the surface area has increased. This causes the parachuter to decele­rate.
pressure is a force spread over an area
High Pressure is a force spread over a small area
Low Pressure is a force spread over a large area
P=F/A where P is measured in Pa, F is N, and A is ㎡.


*the speed at which work is done
P=W/T where P is measured in W, W is J, T is s
eg. if you walk up stairs slowly or quickly the same amount of work has been done. However, doing it faster means you have used more power.
Unrelated to Power
-1/2 the accele­ration means twice the mass
-Accel­eration in freefall has a value equal to the strength of gravity and so is 10ms-2 on Earth
-Weight and gravity force have the same value


-forces can be a push, pull, twist, or turn.
-forces are measured in Newtons (N)
-when the forces on an object are unbala­nced, that object moves
-only commen­t/draw uneven forces unless told otherwise
-always have arrows pointing away from the object
-always have arrows touching the object
the forces are thrust, friction, gravity, and air resistance or support
balanced forces mean the object is stationary or travelling at constant speed
unbalanced forces mean the object will either speed up, slow down, or change direction


is measured in Joules, J
-Kinetic Energy is the energy possessed by a moving object
-the more mass the object obtains and the faster it moves, the more kinetic energy it has
-Gravit­ational Potential Energy is the energy stored in an object because it has been raised a certain height above the ground against the force of gravity
Types of Energy
non-stored energy:
stored­/po­tential energy:
- light and sound
-gravi­tat­ional (height)
-kinetic (movement)
-elastic (spring)
-nuclear (atoms)
-chemical (batte­ries)
Conser­vation of Energy
energy is neither created nor destroyed, it is only transf­erred from one state to another
when energy is converted from one form to another, a proportion is lost as heat and sound energy due to the force of friction


No comments yet. Add yours below!

Add a Comment

Your Comment

Please enter your name.

    Please enter your email address

      Please enter your Comment.

          Related Cheat Sheets

          Chemistry Cheat Sheet

          More Cheat Sheets by liviabrookes

          Genetics Cheat Sheet
          Demand Cheat Sheet
          Supply Cheat Sheet