- To calculate speed you divide distance by time.
- Speed is the rate of change distance travelled.
- Distance is the space between two objects or points.
- Precision is the number of significant digits to which a value may be measured reliably.
- Maximum velocity is fastest speed.
- Average speed is the overall speed.
- Accuracy is how close the result of a measurment or calculation is to the correct value.
- Speed can be measured in mph, kph, m/s.
- Time= distance/ speed.
- Instantaneous is when you do somehting instantly.
- Distance= speed X time
- A distance time graph tells the story of a journey- It shows where the traveller stops. The gradient can tell us the instantaneous speed. The steeper the graph the higher the speed. You can also work out the average speed
- Velocity is speed in a particular direction
- Acceleration is an increase in the speed
- Aerodynamic is being streamlined while going down
- Streamlined is having shape which reduces the drag
- Deceleration is the the speed slowing down
The main forces are-
Net force is the combined force.
- The arrows on a force diagram show you the direction and the size.
Air and Water Resistance is another name for drag it pulls back the object. to increase drag give the object a larger surface area and to decrease it give it a smaller area.
- Air resistance acts with air particles
- Water resistance acts with water particles
Friction is a force between two surfaces.
Newton's First law is-
If the forces acting on a body are balanced then the body either remains still or at terminal velocity.
Newton's Second Law-
If the forces acing on a the body are unbalanced then the body will move in the direction of the largest force.
- Pressure is measured in N/m squared
- To calculate pressure force/ area
- To calculate area force/ pressure
- To calculate force pressure X area
Moments and Levers
A lever is a simple machine which uses a pivot. A pivot is the point around which something turns. We use many levers in everyday life.
When a force is applied to a lever, a turning effect called a moment is made.
- Moment= force X distance
- Force= moment/ distance
- Distance= moment/ force
Total of anticlockwise moments= total of clockwise moments (balanced)