Physics 0625 · IGCSE · Transfer of thermal energy

Transfer of thermal energy — practice question

A boy dives into an indoor swimming pool. As he moves further below the water surface, he observes that the water seems colder. This happens because of convection. Which statement is correct?

  • ACold water is more dense than warm water so it sinks to the bottom of the pool.
  • BWarm water is more dense than cold water so it rises to the surface of the pool.
  • CThe molecules in cold water have more kinetic energy than the molecules in warm water so they move to the bottom of the pool faster.
  • DThe molecules in warm water are closer together than the molecules in cold water so they rise to the surface of the pool.

Worked solution & mark scheme

This 1-mark question has a full step-by-step worked solution and mark scheme.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI