This document discusses distance-time graphs, velocity-time graphs, and standard units for physical properties. Distance-time graphs show steep lines for fast speeds, shallow lines for slow speeds, and flat lines for zero speed. Velocity is calculated from the gradient of a distance-time graph. Velocity-time graphs show increasing, decreasing, or constant speed. The area under a velocity-time graph equals the distance travelled. Common units for physical properties like distance, time, speed, and mass are also listed.

1. DISTANCE-TIME GRAPHS X t X t X t A steep line indicates a fast speed A shallow graph indicates a slow speed A flat line indicates zero speed, the object is stationary

2. DISTANCE-TIME GRAPHS Velocity = 10 m/s The gradient of a distance-time graph = velocity rise run gradient = rise run = 20m 2s = 10

3. VELOCITY-TIME GRAPHS V t V t V t Speed increasing Speed decreasing Constant speed

4. VELOCITY-TIME GRAPHS Distance travelled = 125 m The area under a velocity-time graph = distance travelled area = b x h 2 = 5 x 50 2 = 125

5. PHYSICAL PROPERTIES AND STANDARD UNITS PROPERTY SYMBOL UNIT SYMBOL distance x metres m time t seconds s speed velocity v metres per second m/s ms -1 acceleration a metres per second per second m/s 2 ms -2 mass m kilograms kg force F newtons N energy E joules J