DYNAMICS
In this area, the topics covered are: vectors and scalars; velocity–time graphs; acceleration; Newton’s laws; energy; projectile motion.
SUB UNIT HEADING |
DETAILS |
Vectors and scalars |
- Definition of vector and scalar quantities. - Identification of force, speed, velocity, distance, displacement, acceleration, mass, time and energy as vector or scalar quantities. - Calculation of the resultant of two vector quantities in one dimension or at right angles. - Determination of displacement and/or distance using scale diagram or calculation. - Determination of velocity and/or speed using scale diagram or calculation. - Use of appropriate relationships to solve problems involving velocity, speed, displacement, distance and time. s = v t s= ̅v t d = ̅v t Description of experiments to measure average and instantaneous speed. |
Velocity–time graphs |
- Drawing or sketching of velocity–time or speed–time graphs from data. - Interpretation of a velocity–time graph to describe the motion of an object. - Determination of displacement from a velocity–time graph. s = area under v/t graph. |
Acceleration |
- Definition of acceleration in terms of initial velocity, final velocity and time. - Use of an appropriate relationship to solve problems involving acceleration, initial velocity (or speed), final velocity (or speed) and time. a = (v-u)/t - Determination of acceleration from a velocity–time graph. gradient of the line on a v/t graph. - Description of an experiment to measure acceleration. |
Newton’s laws |
- Application of Newton’s laws and balanced forces to explain constant velocity (or speed), making reference to frictional forces. - Application of Newton’s laws and unbalanced forces to explain and/or determine acceleration for situations where more than one force is acting. - Use of an appropriate relationship to solve problems involving unbalanced force, mass and acceleration for situations where one or more forces are acting in one dimension or at right angles. F = ma - Use of an appropriate relationship to solve problems involving weight, mass and gravitational field strength. W = mg - Explanation of motion resulting from a ‘reaction’ force in terms of Newton’s third law. - Explanation of free-fall and terminal velocity in terms of Newton’s laws |
Energy |
- Explanation of energy conservation and of energy conversion and transfer. - Use of an appropriate relationship to solve problems involving work done, unbalanced force and distance/displacement. Ew = Fd or W = Fd - Definition of gravitational potential energy. - Use of an appropriate relationship to solve problems involving gravitational potential energy, mass, gravitational field strength and height. Ep = mgh - Definition of kinetic energy. - Use of an appropriate relationship to solve problems involving kinetic energy, mass and speed. Ek=1/2 mv^2 - Use of appropriate relationships to solve problems involving conservation of energy. Ew = Fd or W = Fd Ep = mgh Ek=1/2 mv^2 |
Projectile motion |
- Explanation of projectile motion in terms of constant vertical acceleration and constant horizontal velocity. - Use of appropriate relationships to solve problems involving projectile motion from a horizontal launch, including the use of motion graphs. area under v/t graphs (horizontal range) - for horizontal velocity area under v/t graphs (vertical height) - for vertical velocity v = s/t (constant horizontal velocity) - for horizontal velocity v = u + at (constant vertical acceleration) - for vertical velocities - Explanation of satellite orbits in terms of projectile motion, horizontal velocity and weight. |
Summary Notes & Questions
Remember to continual check your past paper attempts and review unknown areas with your summary notes. Websites like BBC Bitesize and Mr MacKenzie Fizzics will also help your revision. Ask your teacher if you are unsure of how to proceed with your revision plan and to clarify areas you are unsure about.