## Overview This topic covers rectilinear and projectile motion. Learners study accelerated motion in a straight line; the motion of bodies falling in a gravitational field; the independence of vertical and horizontal motion of a body moving freely under gravity. ## Working Scientifically This unit contains opportunities for learners to use stopwatches or light gates for timing; to use analogue apparatus to record a range of measurements; to make and record observations; to keep appropriate records and to present data in a scientific way. ## Mathematical Skills There are a number of opportunities for the development of mathematical skills in this unit. These include recognising and making use of appropriate units in calculations; using expressions in decimal and standard form; changing the subject of an equation; substituting numerical values into algebraic equations using appropriate units for physical quantities. ## How Science Works There are opportunities within this topic for learners to use appropriate methodology, including ICT to answer scientific questions and solve scientific problems; to analyse and interpret data to provide evidence, recognise correlations and causal evidence. Learners can carry out experimental and investigative activities using air tracks, light gates, data loggers and photographic or video techniques to investigate factors affecting terminal velocity, stopping distances and the measuring of the speed of moving objects. Learners can apply these factors to consider the possibility of increasing the legal motorway speed limit to 80 mph by analysing data to provide them with evidence to be able to make an informed judgement of whether to support this possibility, or not. ### Learners should be able to demonstrate and apply their knowledge and understanding of: (a) what is meant by displacement, mean and instantaneous values of speed, velocity and acceleration (b) the representation of displacement, speed, velocity and acceleration by graphical methods (c) the properties of displacement-time graphs, velocity-time graphs, and interpret speed and displacement-time graphs for non-uniform acceleration (d) how to derive and use equations which represent uniformly accelerated motion in a straight line (e) how to describe the motion of bodies falling in a gravitational field with and without air resistance - terminal velocity (f) the independence of vertical and horizontal motion of a body moving freely under gravity (g) the explanation of the motion due to a uniform velocity in one direction and uniform acceleration in a perpendicular direction, and perform simple calculations ## [[Specified Practical Work]] - [[Measurement of g by freefall]]