Learning Paths
Each learning path is one chapter: a guided route through a topic, one small course at a time. Pick a class to see its chapters in order.
Chapter 5
Work, Energy and Power, Momentum and Collisions
A roller coaster climbs slowly, and then it races down. A bat hits a ball, and the ball flies away. A motor lifts a load in one minute, and a bigger motor does it in ten seconds. In each case, energy goes from one place or form to another. In this chapter we learn what work is, how it changes the motion of a body, how energy is stored and kept, how fast work is done, and what happens in a collision. Python adds up the work, draws the energy graphs and solves the collisions.
3 courses
Chapter 7
Gravitation, Work, Energy and Power, Circular Motion
An apple falls, the Moon goes round the Earth, and the Earth goes round the Sun. Newton saw that one law of gravitation explains all three. In this chapter we start from the laws that Kepler found in the observations of the planets, we write the law of gravitation, we find how gravity changes above and below the surface, we find the energy that is needed to leave the Earth, and we study satellites, from the Moon to a weather satellite, and the weightlessness of an astronaut. Python solves the orbits and the energy.
3 courses
Chapter 8
Elasticity and Mechanical Properties of Solids, Pressure and Fluids, Work, Energy and Power
A steel cable holds a lift, a bridge bends a little under a lorry, and a rubber band snaps back. A solid changes its shape when we push, pull or twist it, and it comes back when we let it go. In this chapter we measure how much a solid changes, with stress and strain, we find the three moduli of elasticity that describe steel, copper or rubber, we find the energy that is stored in a stretched wire, and we use all this to choose the rope of a crane and the beam of a bridge. Python fits the moduli and designs the beams.
3 courses
Chapter 4Contains Standard content
Work, Energy and Power
You push a heavy cart and you get tired. You sit and read for an hour, and you are tired too. Which one is work in physics? In this chapter we learn what work is and how we measure it. Then we meet energy, the stored ability to do work, and we follow it as it changes from one form to another. We end with power and the unit that appears on an electricity bill. Python helps us with the calculations.
4 courses