Contents Introduction
vii
Chapter 5: Work, energy and power
69
How to use this book
viii
Doing work, transferring energy Gravitational potential energy Kinetic energy g.p.e.–k.e. transformations Down, up, down – energy changes Energy transfers Power
71 75 76 76 77 78 80
Chapter 1: Kinematics – describing motion Speed Distance and displacement, scalar and vector Speed and velocity Displacement–time graphs Combining displacements Combining velocities
Chapter 2: Accelerated motion
1 2 4 5 6 8 10
14
The meaning of acceleration Calculating acceleration Units of acceleration Deducing acceleration Deducing displacement Measuring velocity and acceleration Determining velocity and acceleration in the laboratory The equations of motion Deriving the equations of motion Uniform and non-uniform acceleration Acceleration caused by gravity Determining g Motion in two dimensions – projectiles Understanding projectiles
18 20 22 24 25 25 28 29
Chapter 3: Dynamics – explaining motion
37
Calculating the acceleration Understanding SI units The pull of gravity Mass and inertia Top speed Moving through fluids Identifying forces Newton’s third law of motion
Chapter 4: Forces – vectors and moments Combining forces Components of vectors Centre of gravity The turning effect of a force The torque of a couple
15 15 16 17 17 18
38 39 41 43 44 45 47 49
53 54 56 59 59 63
Chapter 6: Momentum The idea of momentum Modelling collisions Understanding collisions Explosions and crash-landings Collisions in two dimensions Momentum and Newton’s laws Understanding motion
Chapter 7: Matter and materials Density Pressure Compressive and tensile forces Stretching materials Elastic potential energy
Chapter 8: Electric fields Attraction and repulsion The concept of an electric field Electric field strength Force on a charge
Chapter 9: Electric current, potential difference and resistance
85 86 86 89 91 93 95 96
101 102 102 104 105 108
116 117 118 119 122
127
Circuit symbols and diagrams Electric current An equation for current The meaning of voltage Electrical resistance Electrical power
128 129 132 134 135 136
Chapter 10: Kirchhoff’s laws
143
Kirchhoff’s first law Kirchhoff’s second law Applying Kirchhoff’s laws Resistor combinations
144 145 146 148
iii