A metal block of mass 5 kg is heated, and its temperature increases by 15°C. If the specific heat capacity of the metal is 900 J/kg°C, what is the thermal energy change (Temperature changes in a system and specific heat capacity)

The correct answer is 67,500 J.

Boundary lens: Keep this separate from nearby specification points that use similar words but test a different idea. This question asks: A metal block of mass 5 kg is heated, and its temperature increases by 15°C. If the specific heat capacity of the metal is 900 J/kg°C, what is the thermal energy change (Temperature changes in a system and specific heat capacity). The correct response is 67,500 J, because density links mass and volume, so the answer must preserve which quantity is being calculated. In Temperature changes in a system and specific heat capacity, the marking point should connect directly to calculate thermal energy change when mass, specific heat capacity and temperature change are known. If the question includes values, the working must keep the appropriate unit and operation; if it is an explanation, it must name the relevant particle behaviour or energy change. This item belongs to Internal energy and energy transfers, so avoid answers that switch to a different quantity, confuse heat with temperature, or describe gas pressure without collisions when collisions are the reason. Checkpoint 298 is distinct because it uses this exact question context and the boundary lens rather than a generic particle-model sentence.