This key facts covers Sources of Error in the SHC Practical within Specific Heat Capacity for GCSE Physics. Revise Specific Heat Capacity in Energy for GCSE Physics with 15 exam-style questions and 13 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 8 of 15 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 8 of 15
Practice
15 questions
Recall
13 flashcards
⚠️ Sources of Error in the SHC Practical
Why your calculated SHC will probably be TOO HIGH:
- Heat loss to surroundings — not all energy goes into the block
- Your measured ΔE is higher than energy actually absorbed by block
- Since c = ΔE/(mΔθ), overestimating ΔE gives overestimated c
How to improve accuracy:
- Insulate the block — wrap in cotton wool to reduce heat loss
- Use oil in thermometer hole — better thermal contact
- Wait for thermal equilibrium — temperature keeps rising briefly after heater off
- Start below room temperature — heat gains balance heat losses
Quick Check: Calculate the energy needed to heat 2 kg of water from 20°C to 100°C. (SHC of water = 4200 J/kg°C)
ΔE = mcΔθ = 2 × 4200 × (100 − 20) = 2 × 4200 × 80 = 672,000 J (or 672 kJ)