Kinematics JPJC Notes

Kinematics Lecture Note 2023/JPJC/H2 Physics 1 JURONG PIONEER JUNIOR COLLEGE 9749 H2 PHYSICS/ 8867 H1 PHYSICS KINEMATICS Content  Rectilinear motion  Non-linear motion Learning Outcomes Candidates should be able to: (a) show an understanding of and use the terms distance, displacement, speed, velocity and acceleration. (b) use graphical methods to repres ent distance , displacement, speed, velocity and acceleration. (c) identify and use the physical quantities from the gradients of displacement-time graphs and areas under and gradients of velocity-time graphs, including cases of non-uniform acceleration. (d) derive, from the definitions of velocity and acceleration, equations which represent uniformly accelerated motion in a straight line. (e) solve problems using equations which represent uniformly accelerated motion in a straight line, including the motion of bodies falling in a uniform gravitational field without air resistance. (f) describe qualitatively the motion of bodies falling in a uniform gravitational field with air resistance. (g) describe and explain motion due to a uniform velocity in one direction and a uniform acceleration in a perpendicular direction. Introduction The study of physics often begins with Newtonian Mechanics which investigates relationships between force and motion. The study of motion can be divided into two aspects: how objects move (kinematics) and why objects move in different ways (dynamics). Models and representations such as motion diagrams, graphs and equations are used to quantify, describe and predict motion. Motion in the real world is rather complex. The study of motion at this level is made simple with the use of assumptio ns. One valid assumption is to model the moving body as a point with no size where effects such as rotation or change of shape are not considered. It is also appropriate to ignore air resistance in solving most problems. Key Questions: 1. How do we describe the motion of objects? 2. How can the motion of objects be represented, quantified and predicted? 3. How can we tell if an object is moving with a constant acceleration? 4. For an object falling freely in a gravitational field, how would it move?

Kinematics Lecture Note 2023/JPJC/H2 Physics 2 1 Kinematics Quantities (a) Show an understanding of and use the terms distance, displacement, speed, velocity and acceleration. 1.1 Distance and Displacement Distance travelled (scalar) is the total length moved along the path of motion. Displacement (vector) is the linear distance in a specified direction from a reference point. Example 1 A man at point A travels 4.0 km due East to point B. He then travels a further 3.0 km due North to point C. Determine the total distance travelled and his displacement from the original position (point A). 1.2 Speed and Velocity Speed (scalar) is the r