Physical Sciences Grade 10 Term 3 Revision Booklet PDF

Western Cape Education Department Directorate: Curriculum FET PHYSICAL SCIENCES REVISION BOOKLET TERM 3 Grade 10 This revision program is designed to assist...

Western Cape Education Department Directorate: Curriculum FET PHYSICAL SCIENCES REVISION BOOKLET TERM 3 Grade 10 This revision program is designed to assist you in revising the critical content and skills covered during the 2nd term. The purpose is to prepare you to understand the key concepts and to provide you with an opportunity to establish the required standard and the application of the knowledge necessary to succeed.  Terminology Vector A physical quantity that has a magnitude, a unit and direction. Scalar A physical quantity that has a magnitude and a unit. Resultant Vector A single vector that has the same effect as two or more vectors. Reference Point A point from which the position of an object is measured. Frame of A set of reference points that enables the position of an object to be Reference exactly defined at any given time. Position The place where an object is relative to a reference point within a frame of reference. Displacement The change in position with respect to the starting point. Distance The length of the path followed by an object. Velocity The rate of change of an object’s position. Average Velocity The total displacement divided by the total time taken. Instantaneous The displacement divided by an infinitesimal small time interval Velocity Speed The rate at which an object covers a distance. Average Speed The total distance travelled divided by the total time taken Instantaneous The distance divided by an infinitesimal small time interval Speed Acceleration The rate of change of velocity of an object. Braking distance The distance it takes an object to come to a stop. Thinking distance The distance the car travels while the driver is reacting to a situation. Stopping The total distance a car needs to come to a stop. distance 2 Vectors: The basics The most important aspect of vectors is direction. Within your frame of reference, you need to choose one direction as positive. The opposite direction is then negative. Example: John walks 5 m to the right and then walks 2 m to the left. If right is positive, then John walks +5 m and then walks – 2 m You MUST always indicate which direction you choose as positive. Differences between Vectors and Scalars Scalar quantities can be added and subtracted just like ordinary numbers. When we add vectors, the direction must be included by assigning a sign (+ or -) to the value. Direction of a vector The direction of a vector can be indicated in various ways. 1. By using a description, like to the left or right, up and down, towards or away from you, etc. y 2. The direction of a vector can also be specified relative to the x or y-axis. 30° The direction of this vector is, for example, x 30° to the right of the positive y-axis. 3. By using compass bearings N 45⁰ North of east W O 4. By using the base line. The base line is a vertical line. S All directions are measured clockwise from this line. Do not confuse it with Maths in which angles are measured anti-clockwise from a horizontal line. Base line 30° 300° Bearing 30º Bearing 300 º 3  Graphical Representation of vectors 1. Scale vector diagrams Vectors are drawn accurately to scale Choose a scale Length of arrow = magnitude of vector Direction of arrow = direction of vector Always label your vectors 2. Sketch vector diagrams Vectors are not drawn to scale Length of arrow indicates magnitude of vector Direction of arrow = direction of vector Always label your vectors Addition of vectors 1. Choose a direction as positive 2. Write a formula to show you are adding all the vectors 3. Substitute your vectors, using the sign to show in which direction the vector is acting 4. Calculate the resultant vector 5. Remember to add a unit AND a direction Scalar multiplication of vectors 1. 3F = multiply the magnitude by 3 and vector is in the same direction 2. ⅓F = divide the magnitude by 3 and vector is in the same direction 3. -3F = multiply the magnitude by 3 and the vector is in the opposite direction 4. -⅓F = divide the magnitude by 3 and the vector is in the opposite direction 4 Position (x) The position in a frame of reference relative to the reference point Vector Displacement (∆x) The change of position of an object in a frame of reference relative to the reference point Vector Distance (d) The length of the pathway followed by an object Scalar Velocity (v) The rate of change of displacement of an object Vector ∆x v ∆t Speed (v) The rate of change of distance of an object Scalar ∆d v ∆t 5 Acceleration (a) The rate of change of velocity of an object Vector ∆v a ∆t Graphs of motion 3 types of motion: 1. Stationary objects 2. Objects moving at constant velocity 3. Objects moving at constant acceleration 3 types of graphs 1. Position vs Time 2. Velocity vs Time 3. Acceleration vs Time Graphs must have a heading Both axis must be labelled with units x-axis = independent variable y-axis = dependent variable Clearly show all points you are plotting Draw the line of best fit 6 Stationary Objects Acceleration (m.s-2) Velocity (m.s-1) Position (m) Time (s) Time (s) Time (s) Position stays constant Velocity = 0 Acceleration = 0 Objects moving at Constant Velocity Acceleration (m.s-2) Velocity (m.s-1) Position (m) Time (s) Time (s) Time (s) Position changes at a Velocity stays constant Acceleration = 0 constant rate Objects moving at Constant Acceleration Acceleration (m.s-2) Velocity (m.s-1) Position (m) Time (s) Time (s) Time (s) 7 Equations of Motion Road safety Braking distance: The distance it takes an object to come to a stop. Most cars have a maximum acceleration of -6 m.s-2 Thinking distance: The distance the car travels while the driver is reacting to a situation. The average reaction time between realising that there has been a change in traffic and deciding to do something about it is 0,75 s. The average reaction time between deciding to do something and your body being able to do it is 0,75 s. The average human therefore takes 1,5 s to react. Stopping distance: The total distance a car needs to come to a stop. Stopping distance = braking distance + thinking distance 8 Questions: DBE Grade 10 November 2015 Paper 1 9 10 11 DBE Grade 10 November 2016 Paper 1 12 13 14 15 16 17 DBE Grade 10 November 2017 Paper 1 18 19 20 21 22 23 DBE Grade 10 November 2018 Paper 1 24 25 26 27 28