Definitions
Words Markscheme definition
Specific heat capacity The energy required to change the temperature of a substance by 1 K of 1 kg
Internal energy Sum of the total kinetic and potential energies of the atoms / particles /
molecules of a substance
Specific latent heat of The energy required to change the phase of 1 kg of a substance from a solid to a
fusion liquid without any temperature change
Simple harmonic motion The (restoring) force / acceleration is proportional to the displacement from
equilibrium. The force / acceleration is directed toward the equilibrium; the
force / acceleration is in the opposite direction to the displacement
Longitudinal wave The direction of oscillations / vibrations/ movement of particles; for a
longitudinal wave is parallel to the direction of energy propagation of the ave
Explain why intensity Two waves superpose; they arrive in phase / there is a path length difference of
maxima are observed an integer of a wavelength
Drift velocity in Electrons have high random speeds when accelerated by an electric field in a
conduction conductor. They collide with the ions and obtain a net speed in the direction
opposite to the field direction
Coulomb’s law The force between two point charges is inversely proportional to the square of
their separation and directly proportional to the product of their magnitudes;
OR equation with the variables defined
Electromotive force Work per unit charge supplied (by a cell) driving the current completely around
a circuit; potential difference across a cell when no current flows
Discuss why there is a Electrons are free moving in the copper wires so they are able to carry current;
significant electric charge carriers are not free moving in the insulator; when an electric field is
current only in the applied, it will accelerate the free moving electrons
copper wires
Explain in terms of There will be a greater vibration of the lattice ions; drift velocity of the
electrons what happens electrons decreases; voltage is constant so resistance increases
to the resistance of the
cable as the temperature
of the cable increases
Explain why centripetal Circular motion involves a changing velocity that is tangential and
force is required to keep perperpendicular to the centripetal force. Without centripetal force, the planet
Words Markscheme definition
Specific heat capacity The energy required to change the temperature of a substance by 1 K of 1 kg
Internal energy Sum of the total kinetic and potential energies of the atoms / particles /
molecules of a substance
Specific latent heat of The energy required to change the phase of 1 kg of a substance from a solid to a
fusion liquid without any temperature change
Simple harmonic motion The (restoring) force / acceleration is proportional to the displacement from
equilibrium. The force / acceleration is directed toward the equilibrium; the
force / acceleration is in the opposite direction to the displacement
Longitudinal wave The direction of oscillations / vibrations/ movement of particles; for a
longitudinal wave is parallel to the direction of energy propagation of the ave
Explain why intensity Two waves superpose; they arrive in phase / there is a path length difference of
maxima are observed an integer of a wavelength
Drift velocity in Electrons have high random speeds when accelerated by an electric field in a
conduction conductor. They collide with the ions and obtain a net speed in the direction
opposite to the field direction
Coulomb’s law The force between two point charges is inversely proportional to the square of
their separation and directly proportional to the product of their magnitudes;
OR equation with the variables defined
Electromotive force Work per unit charge supplied (by a cell) driving the current completely around
a circuit; potential difference across a cell when no current flows
Discuss why there is a Electrons are free moving in the copper wires so they are able to carry current;
significant electric charge carriers are not free moving in the insulator; when an electric field is
current only in the applied, it will accelerate the free moving electrons
copper wires
Explain in terms of There will be a greater vibration of the lattice ions; drift velocity of the
electrons what happens electrons decreases; voltage is constant so resistance increases
to the resistance of the
cable as the temperature
of the cable increases
Explain why centripetal Circular motion involves a changing velocity that is tangential and
force is required to keep perperpendicular to the centripetal force. Without centripetal force, the planet
