Physics

Pupils will be taught about:

Energy

Calculation of fuel uses and costs in the domestic context

Energy changes and transfers

simple machines give bigger force but at the expense of smaller movement (and vice versa): product of force and displacement unchanged
heating and thermal equilibrium: temperature difference between two objects leading to energy transfer from the hotter to the cooler one, through contact (conduction) or radiation; such transfers tending to reduce the temperature difference: use of insulators
other processes that involve energy transfer: changing motion, dropping an object, completing an electrical circuit, stretching a spring, metabolism of food, burning fuels.

Changes in systems

energy as a quantity that can be quantified and calculated; the total energy has the same value before and after a change
comparing the starting with the final conditions of a system and describing increases and decreases in the amounts of energy associated with movements, temperatures, changes in positions in a field, in elastic distortions and in chemical compositions
using physical processes and mechanisms, rather than energy, to explain the intermediate steps that bring about such changes.

Motion and forces

Describing motion

speed and the quantitative relationship between average speed, distance and time (speed = distance ÷ time)
the representation of a journey on a distance-time graph
relative motion: trains and cars passing one another.

Forces

forces as pushes or pulls, arising from the interaction between two objects
using force arrows in diagrams, adding forces in one dimension, balanced and unbalanced forces
moment as the turning effect of a force
forces: associated with deforming objects; stretching and squashing – springs; with rubbing and friction between surfaces, with pushing things out of the way; resistance to motion of air and water
forces measured in newtons, measurements of stretch or compression as force is changed
force-extension linear relation; Hooke’s Law as a special case
work done and energy changes on deformation
non-contact forces: gravity forces acting at a distance on Earth and in space, forces between magnets and forces due to static electricity.

Pressure in fluids

atmospheric pressure, decreases with increase of height as weight of air above decreases with height
pressure in liquids, increasing with depth; upthrust effects, floating and sinking
pressure measured by ratio of force over area – acting normal to any surface.

Balanced forces

opposing forces and equilibrium: weight held by stretched spring or supported on a compressed surface.

Forces and motion

forces being needed to cause objects to stop or start moving, or to change their speed or direction of motion (qualitative only)
change depending on direction of force and its size.

Waves

Observed waves

waves on water as undulations which travel through water with transverse motion; these waves can be reflected, and add or cancel – superposition.

Sound waves

frequencies of sound waves, measured in hertz (Hz); echoes, reflection and absorption of sound
sound needs a medium to travel, the speed of sound in air, in water, in solids
sound produced by vibrations of objects, in loud speakers, detected by their effects on microphone diaphragm and the ear drum; sound waves are longitudinal
auditory range of humans and animals.

Energy and waves

pressure waves transferring energy; use for cleaning and physiotherapy by ultra-sound; waves transferring information for conversion to electrical signals by microphone.

Light waves

the similarities and differences between light waves and waves in matter
light waves travelling through a vacuum; speed of light
the transmission of light through materials: absorption, diffuse scattering and specular reflection at a surface
use of ray model to explain imaging in mirrors, the pinhole camera, the refraction of light and action of convex lens in focusing (qualitative); the human eye
light transferring energy from source to absorber leading to chemical and electrical effects; photo-sensitive material in the retina and in cameras
colours and the different frequencies of light, white light and prisms (qualitative only); differential colour effects in absorption and diffuse reflection.

Electricity and electromagnetism

Current electricity

electric current, measured in amperes, in circuits, series and parallel circuits, currents add where branches meet and current as flow of charge
potential difference, measured in volts, battery and bulb ratings; resistance, measured in ohms, as the ratio of potential difference (p.d.) to current
differences in resistance between conducting and insulating components (quantitative).

Static electricity

separation of positive or negative charges when objects are rubbed together: transfer of electrons, forces between charged objects
the idea of electric field, forces acting across the space between objects not in contact.

Magnetism

magnetic poles, attraction and repulsion
magnetic fields by plotting with compass, representation by field lines
earth’s magnetism, compass and navigation
the magnetic effect of a current, electromagnets, D.C. motors (principles only).

Matter

Physical changes

conservation of material and of mass, and reversibility, in melting, freezing, evaporation, sublimation, condensation, dissolving
similarities and differences, including density differences, between solids, liquids and gases
Brownian motion in gases
diffusion in liquids and gases driven by differences in concentration
the difference between chemical and physical changes.

Particle model

the differences in arrangements, in motion and in closeness of particles explaining changes of state, shape and density, the anomaly of ice-water transition
atoms and molecules as particles.

Energy in matter

Space physics

gravity force, weight = mass x gravitational field strength (g), on Earth g=10 N/kg, different on other planets and stars; gravity forces between Earth and Moon, and between Earth and Sun (qualitative only)
our Sun as a star, other stars in our galaxy, other galaxies
the seasons and the Earth’s tilt, day length at different times of year, in different hemispheres
the light year as a unit of astronomical distance.