Doc Brown's Edexcel GCSE Science-Physics
Revision Notes STUDY NOTES
Edexcel GCSE Science GCSE Physics Unit P1 Universal physics
Physics Unit P1 Topic 4 Waves and the Earth
4.1 Know that sound with frequencies greater than 20 000 hertz, Hz, is
known as ultrasound.
4.2 Be able to describe some uses of ultrasound, including:
- a) sonar
communication between animals
- c) foetal scanning
4.3 Be able to calculate depth or distance (d
from time (s) and velocity (m/s) of ultrasound
- using the formula: v = d / t, so
rearranging gives d = v x t
- 4.4 Know that sound with frequencies less than
20 hertz, Hz, is known as infrasound.
- 4.5 Be able to describe uses of infrasound, including:
- a) communication between animals
- b) detection of animal movement in remote
- c) detection of volcanic eruptions and meteors
- 4.6 Know that seismic
waves are generated by earthquakes or explosions
- 4.7 Revise any investigation you did into the
unpredictability of earthquakes, using sliding blocks and weight.
- 4.8 Be able to explain
why scientists find it difficult to predict earthquakes and tsunami waves even
with available data.
- 4.9 Know that seismic waves can be longitudinal (P) waves
and transverse (S) waves and that they can be reflected and refracted at
boundaries between the crust, mantle and core.
- 4.10 Be able to explain how data from
seismometers can be used to identify the location of an earthquake.
HT only: Be able to show an understanding of how P and S waves travel inside the Earth
including reflection and refraction.
- 4.12 Be able to explain how the Earth’s outermost layer
is composed of (tectonic) plates and is in relative motion due to convection
currents in the mantle.
- 4.13 You must have an understanding of how, at plate
boundaries, plates may slide past each other, sometimes causing earthquakes.