Conduction

One end of a solid bar is heated. By what process is thermal energy moved to the opposite end of the bar?

May/June 2015

A metal bar with a solid structure is heated at one end. By what process is thermal energy passed to the opposite end of the bar?

May/June 2015

Four samples of different materials at room temperature are heated from underneath, and heat moves upward. In which material is all of the heat carried by molecular vibration?

May/June 2018

A student is given two metal rods: one is copper and the other is iron. She carries out an experiment to find out which metal conducts heat better. She places the rods across a heat-proof mat on a tripod stand, with the rods touching at one end, as shown in Fig. 1.1. At the other end of each rod, she attaches a drawing pin using a small blob of wax that has a low melting point. She then heats the ends where the rods touch, as shown.

May/June 2018

One end of a copper rod is heated. Which statement explains how heat transfer takes place in the copper?

May/June 2021

Heat is applied to one end of a copper rod. Which statement describes the process by which heat is transferred through the copper?

May/June 2021

A building has walls made from wood and steel. What term describes the transfer of thermal energy through the walls?

May/June 2022

A cold solid is put above a hot solid. Thermal energy moves from the hot solid into the cold one. What explains this?

May/June 2023

Which statement about copper helps to explain why it is a better conductor of thermal energy than glass?

May/June 2023

A student carries out an investigation into how long ice cubes take to melt when they are put into a beaker of hot water.

May/June 2023

An ice-filled pan at $-15^\circ\text{C}$ is shown in Fig. 3.1 and is resting on a gas heater.

May/June 2024

Thermal energy is transferred rapidly from the hotter parts of a metal to the cooler parts of the metal. Why do metals make good conductors of thermal energy?

May/June 2025

The diagram depicts a metal pan resting on a hotplate. The hotplate supplies heat to the pan. How is thermal energy passed from the hotplate to the metal pan?

May/June 2025

In which substance is thermal energy conduction mainly caused by the motion of electrons?

Oct/Nov 2017

A cold solid is put on top of a hot solid. Thermal energy moves from the hot solid to the cold solid. What explains this?

Oct/Nov 2018

Solid metals are efficient conductors of thermal energy. How tightly packed are the particles, and do metals contain free electrons?

Oct/Nov 2023

Cotton wool acts as a good thermal insulator. It is made up of many cotton fibres that are twisted together to form a material that can be pulled apart easily or compressed. The diagram shows the structure of cotton wool. Why does cotton wool act as a good thermal insulator?

Oct/Nov 2023