9 Thermal Properties and Temperature 2020N

When a bridge is built, a gap is left between each concrete slab. Why are these gaps left?

• Concrete expands on warm days.

• Concrete contracts on warm days.

• The gaps expand on warm days.

• The gaps contract on cold days.

The table shows the melting and boiling points of four different substances.

Which substance becomes a liquid when placed in a beaker of boiling water? .................

Wet clothes are put out on a line to allow the water in the clothes to evaporate. Which type of weather would cause the water to evaporate most quickly?

• a cold day with no wind

• a cold day with wind

• a hot day with no wind

• a hot day with wind

Samples of four different substances are heated in turn by the same heater, for the same time duration and in the same conditions. The increase in temperature for each sample is recorded. Which sample has the highest thermal capacity? ................

Thermal energy is supplied at the same rate to four bars made from different materials. After several minutes, there is a temperature difference between X and Y for each bar.

Which statement identifies the bar with the greatest temperature difference between points X and Y, and gives the correct reason?

• copper because it is a good conductor of thermal energy

• lead because it is the densest metal

• plastic because it is a poor conductor of thermal energy

• wood because it is a good conductor of thermal energy

Which physical property changes when temperature is measured with a liquid-in-glass thermometer?

• electromotive force

• pressure

• resistance

• volume

Two different pure substances X and Y are heated. Both substance X and substance Y are initially in the solid state. The graph shows how the temperature of each substance changes with time.

What does the graph tell us about the substances?

• Substance X has a lower boiling point than substance Y.

• Substance X has a lower melting point than substance Y.

• Substance Y has a lower boiling point than substance X.

• Substance Y has a lower melting point than substance X.

A student splashes water on to her face. Here are three statements about the effects. P The water uses energy to evaporate. Q The water gains energy from the student. R The face of the student cools. Which statements are correct?

• P and Q only

• P and R only

• Q and R only

• P, Q and R

When a bridge is built, a gap is left between each concrete slab. Why are these gaps left?

• Concrete expands on warm days.

• Concrete contracts on warm days.

• The gaps expand on warm days.

• The gaps contract on cold days.

The specific heat capacity of solid P is greater than that of solid Q. What does this statement mean?

• Less energy is needed to raise the temperature by 1°C of unit mass of solid P than unit mass of solid Q.

• Less energy is needed to melt unit mass of solid P than unit mass of solid Q.

• More energy is needed to raise the temperature by 1°C of unit mass of solid P than unit mass of solid Q.

• More energy is needed to melt unit mass of solid P than unit mass of solid Q.