Cambridge IGCSE Physics Notes 1.7: Energy, Work and Power
Cambridge IGCSE Physics notes on energy stores, transfers, work, kinetic and gravitational energy, efficiency, resources, and power.
Q: What does Cambridge IGCSE Physics Notes 1.7: Energy, Work and Power cover?
A: It follows official Cambridge Physics section 1.7 for syllabuses 0625 and 0972, with Core ideas separated from Supplement depth.
Energy is conserved through transfers between stores, while work measures energy transferred by a force and power measures how quickly transfer occurs.
The ideas that organise this section
- Describe an energy transfer by naming the initial store, transfer pathway, and final stores.
- Useful output plus dissipated output equals the total input.
- Resource comparisons require both physical performance and environmental or practical consequences.
Core route
Core candidates should be ready to describe, calculate, interpret, and apply the following:
- Identify energy stores and transfer pathways and apply conservation.
- Calculate work, kinetic energy, gravitational potential energy, power, and efficiency in direct situations.
- Compare renewable and non-renewable energy resources using advantages and disadvantages.
Supplement route
Extended candidates study all Core content and add the following depth:
- Use energy relationships in multi-step problems and explain dissipation.
- Evaluate resource choices using reliability, response time, environmental effects, and location.
- Connect power to both work done and energy transferred per unit time.
Formula route
- Relationship: work done = force x distance moved in force direction.
- Relationship: kinetic energy = 0.5 x mass x speed squared.
- Relationship: gravitational energy change = mass x gravitational field strength x height.
- Relationship: power = work done / time.
- Relationship: efficiency = useful output / total input.
Write the relationship before substituting. Convert units first, keep extra figures during working, and round only the final answer to sensible precision.
Build a connected model
In Energy, Work and Power, a strong answer connects the named quantity or model to observable evidence. Begin by defining the physical quantity in words or with its relationship. Identify which values are scalars and which require a direction. Represent the situation with a labelled diagram, graph, field pattern, ray or circuit when that makes the relationship visible. The representation is part of the reasoning: its labels, arrows and scale should agree with the written explanation.
