# Facts to learn for GCSE Exams

• Symbol for velocity v
• Atmospheric pressure 100000 Pa
• Unit for velocity m/s (metres per second)
• Symbol for length l
• Density of fresh water 1000kg/m3 or 1g/cm3
• Unit for length m (metres)
• Symbol for force F
• Density of sea water 1050 kg/m3
• Unit for force N (Newtons)
• Symbol for acceleration a
• Density of air 1.3 kg/m3
• Unit for acceleration m/s2 (metres per second squared)
• Symbol for mass m
• Acceleration due to gravity on Earth 9.81m/s2
• Gravitational field strength on Earth 9.81N/kg (sometimes 10N/kg)
• Unit for mass kg (kilograms)
• Symbol for time t
• Gravitational field strength on Mars 3.7N/kg
• Unit for time s (seconds)
• Symbol for temperature T
• Acceleration due to gravity on Mars 3.7m/s2
• Unit for temperature °C (or K) (degrees Celsius or Kelvin)
• Symbol for current I
• Gravitational field strength on The Moon 1.6N/kg
• Unit for current A (or K) (Amps)
• Symbol for area A
• Acceleration due to gravity on The Moon 1.6m/s2
• Unit for area m2 (or K) (metres squared)
• Symbol for density ρ
• Specific heat capacity of water 4200J/kg°C
• Unit for density kg/m3 (kilograms per metre cubed)
• Symbol for charge Q
• Specific heat capacity of ice 2100J/kg°C
• Unit for charge C (Coulomb)
• Symbol for energy E
• Specific latent heat of change from ice to water 340000J/kg
• Unit for energy J (Joules)
• Symbol for frequency f
• Specific latent heat of change from water to steam 2260000J/kg
• Unit for frequency Hz (Hertz)
• Symbol for gravitational field strength g
• Mains electricity in homes 230V
• Unit for gravitational field strength N/kg (Newton per kilogram)
• Symbol for moment M
• Mains frequency in homes 50Hz
• Unit for moment Nm (Newton metres)
• Symbol for momentum p
• Voltage that homes and offices receive from the national grid 230V
• Unit for momentum kgm/s (kilogram metres per second)
• Symbol for voltage V
• Voltage that hospitals and schools receive from the national grid 11000V
• Unit for voltage V (Volts)
• Symbol for power P
• Voltage that large factories receive from the national grid 33000V
• Unit for power W (Watt)
• Symbol for pressure P
• The speed of sound in air is 330m/s
• Unit for pressure Pa or N/m2 (Pascals or Newtons per metres squared)
• Unit for radioactivity Bq (Becquerel)
• Symbol for resistance R
• The speed of sound in water is 1500m/s
• Unit for resistance Ω (Ohms)
• Symbol for volume V
• The speed of sound in steel is 5000m/s
• Unit for volume m3 (metres cubed)
• Symbol for distance d or x or s
• The range of human hearing is 20Hz - 20000Hz
• Unit for distance m (metres)
• Symbol for speed s
• All electromagnetic waves travel at the same speed in a vacuum 3.0 x 108m/s
• Unit for speed m/s (metres per second)
• Symbol for weight W
• Critical angle in glass 42°
• Unit for weight N (Newtons)
• Symbol for gravitational potential energy GPE
• Ideal conditions in the Haber process 200atm pressure, 450°C, iron catalyst
• Unit for gravitational potential energy J (Joules)
• Symbol for kinetic energy KE
• Unit for kinetic energy J (Joules)
• Symbol for wavelength λ
• Unit for wavelength m (metres)
• Symbol for work done W or E
• Unit for work done J (Joules)
• Symbol for energy transferred E
• Unit for energy transferred J (Joules)
• Symbol for spring constant k
• Unit for spring constant N/m (Newtons per metre)
• Symbol for potential difference pd
• Unit for potential difference V (Volts)
• Symbol for magnetic flux density B
• Unit for magnetic flux density T or N/Am (Tesla or Newtons per Amp metre)