Level 1 Science
1.1 Mechanic's
AS 90940
External
4 Credit's
This achievement standard involves demonstrating understanding of aspects of mechanics and may include using methods when solving related problems.
Slide 2
Velocity V = D / T
Speed is how fast something is going.
Velocity is how fast something is changing position in a certain amount of time.
Constant Velocity means an objects velocity is not changing.
Non- Constant Velocity means the object is Accelerating or decelerating.
The Gradient of a distance vs time graph is the velocity.
Unit is ms-1
Horizontal Line - Stationary
Straight Line - Constant Speed (If this is sloping down the object will be returning to the start)
Curved line - Accelerating or Decelerating
Unit for Acceleration is ms-2
The triangle means change in so you take the final speed minus the initial speed
The gradient of the speed time graph is the acceleration.
Forces change the speed of an object
Net force is the overall force its like the leftover force when everything else is balanced out.
Weight is the downward force due to gravity (N)
Mass is the amount of matter in an object (kg)
Measured in Newtons (N
Balanced forces are were all the forces cancel out therefore there is no net force and the object is stationary or moving at a constant speed.Unbalanced forces are when the forces dont balance in a certain direction causing a net force which will mean the object is accelerating.
Mass is the amount of matter in an object whereas the weight is the downward force of an object due to gravity. Mass (m) is measured in kgWeight (w or f) is measured N On earth this downward force is 10N.
Energy isn't created or destroyed it can only be transferred into different types of energy.Gravitational Potential EnergyElastic Potential EnergyChemical potential EnergyHeat + Light or Sound EnergyMeasured in joules J (make sure it is a capital)Change into kg first when measuring mass
Power is how much work is being done per second.The unit for power (P) is Watts (W) or Js-1The unit for power is the same for pressure (P) so don't get caught by this. If something has a high power it means it can do a lot of work in a small amount of time.
Pressure deals with force over an area. Small areas have high pressure and large area's have low pressure for the same force. Times or divide cm to get to m either by 100 then 10000 or just 100.