P2. Topic 1- Motion

• Gradient of the line on a distance-time graph represents an object's SPEED.

• The STEEPER the line the GREATER the speed it represents

• Equation: Speed in metres per second, m/s =

                                   distance travelled in metres,m (divide)                                                       time taken in seconds,s

• VELOCITY is SPEED in a given DIRECTION.

• If and object changes direction it also changes Velocity even if the speed is still the same.

• If the Velocity changes then we say that it ACCELERATES.

• ACCELERATION is the change of velocity per second.

• DECELERATION is the same as negative acceleration

• Equation: a =  v - u 
•                        t

• Symbols and meanings:
• a is acceleration in metres per second,m/s²
• v is the final velocity (The velocity we have at the end) in metres per second, m/s
• u is the initial velocity (starting velocity) in metres per second, m/s
• t is the time taken for the change (Make sure to convert from hours to seconds) in seconds,s

• If the line on a velocty-time graph is HORIZONTAL, the acceleration is ZERO therefore the object is travelling at a steady speed.

• The GRADIENT represents acceleration.

• The area under the velocity-time graph is the DISTANCE travelled.(HIGHER)

• If the gradient of the line is NEGATIVE the object is decelerating.

• The SPEED of an object is given by the GRADIENT of the line on its DISTANCE-TIME graph

• The ACCELERATION of an object is given by the GRADIENT of the line on its VELOCITY-TIME graph.