Fig. 1.1 shows galaxies around an observer. The arrows show the direction of motion of each galaxy. What does this observation tell us about the universe?

A house has cavity walls. The cavity is filled with foam that traps many small pockets of air. Which statement best explains how this foam reduces thermal en...

The table shows four safety precautions and the type of radiation each is said to protect against. Which row is correct? Safety precaution Radiation A wearin...

A factory uses a radioactive source to monitor the thickness of metal sheets. The sheets are 5 mm thick. Which type of radiation would be most suitable for t...

A swimmer completes two lengths of a 50 m pool. The table shows her times. Length Distance / m Time / s 1st (outward) 50 32 2nd (return) 50 38 What are the a...

A rubber ball and a clay ball of identical mass are thrown at a wall at the same speed. The rubber ball bounces back; the clay ball sticks. Which ball exerts...

A nuclear fission chain reaction is said to be critical when exactly one neutron from each fission event goes on to cause one further fission. What happens t...

The table shows the specific latent heat of fusion for four metals. Substance Specific latent heat of fusion / kJ/kg aluminium 397 copper 205 iron 247 lead 2...

Table 1.1 shows readings from an experiment where a fixed mass of gas is kept at constant temperature while its volume is changed. Volume / cm3 Pressure / kP...