The diagram represents moving gas molecules in a sealed container of fixed volume. The temperature of the gas is now increased. What happens to the pressure of the gas, and what happens to the speed of the gas molecules?
Pressure: increase, speed: increase
The diagrams represent the molecules in two different states of matter. The arrows show the motion of the molecules. What is state 1, and what is state 2?
state 1: gas; state 2: solid
A substance loses thermal energy (heat) to the surroundings at a steady rate. The graph shows how the temperature of the substance changes with time. What could the portion PQ of the graph represent?
liquid cooling
Which two beakers should she use to check the fixed points?
Q and S
An engineer wants to fix a steel washer on to a steel rod. The rod is just too big to fit into the hole of the washer. How can the engineer fit the washer on to the rod?
Heat the rod and then place it in the hole in the washer.
Why are the cables left loose?
They will expand on very warm days.
What is the main process by which the water at the bottom of the glass becomes cool?
convection
Between which labelled points on the graph is the substance partly solid and partly liquid?
between Q and R
The diagrams show four blocks of steel. The blocks are all drawn to the same scale. The same quantity of thermal energy (heat) is given to each block. Which block shows the greatest rise in temperature?
A
