31 of the Physics glossary’s terms, each with the part of the syllabus where you first meet it.
A conducting enclosure; because the electric field inside a conductor's cavity is zero, it shields its contents from external electric fields.
The emf induced in a circuit equals the rate of change of the magnetic flux linkage through it: .
A force that acts across a distance without contact, even through a vacuum: gravitational, electric and magnetic forces.
A line showing the direction of the force on a test mass (or charge) at each point; the closer the lines, the stronger the field.
A lamp in which a thin tungsten wire glows when heated by a current; its resistance rises as it heats up, so it is non-ohmic.
A glass bulb containing an electron gun and gas at low pressure, in which an electron beam bent into a circle by a magnetic field is made visible by the glowing gas.
The standing wave of lowest frequency that a system can support.
Conservation of energy for a closed system: , where is thermal energy supplied to the system and is work done by it.
The first dark direction either side of the centre of a single-slit pattern, at (radians, small angles), where is the slit width.
Describes a nuclide, such as uranium-235 or plutonium-239, that can undergo fission after absorbing a slow (thermal) neutron.
A nucleus formed when a heavy nucleus splits; fission products are neutron-rich and so are usually radioactive β⁻ emitters.
An end of a string that cannot move, such as a clamp; it is always a node of a standing wave.
A rule for the direction of the magnetic force: with the first finger along the field and the second finger along the conventional current, the thumb points along the force.
The force exerted by a gas or liquid on a body moving through it, opposite to the body's velocity relative to the fluid; it increases with speed.
The product of the number of turns of a coil and the magnetic flux through each turn; measured in webers.
A heavy wheel with a large moment of inertia, used to store energy as rotational kinetic energy or to smooth out changes in rotation.
A push or a pull exerted by one body on another; a vector quantity measured in newtons (N).
An oscillation maintained by a periodic external force; in the steady state the system oscillates at the driving frequency.
A fuel formed over millions of years from the remains of living things, such as coal, oil or natural gas; burning it releases carbon dioxide.
The absolute uncertainty divided by the value, ; it has no unit.
The dark absorption lines in the spectrum of the Sun, produced by elements in its cooler outer layers.
An end of a string that can move freely, such as a light ring sliding on a smooth rod; it is always an antinode of a standing wave.
Motion under the influence of gravity alone, with no other force (such as fluid resistance) acting.
A diagram of one body on its own showing every force that acts on it as a labelled arrow, with lengths roughly in proportion to the forces.
The change from liquid to solid at the melting point, during which energy is released at constant temperature.
The number of oscillations or cycles per unit time; symbol , measured in hertz (Hz), with .
The component of the contact force parallel to two surfaces, which opposes their relative sliding or their tendency to slide.
One of the bright or dark bands in an interference or diffraction pattern.
The distance between the centres of neighbouring bright (or dark) fringes; for a double slit, .
A substance that releases energy in a controlled way, usually by burning or by nuclear reactions.
A sealed metal tube filled with pellets of nuclear fuel (usually uranium dioxide), which keeps the fission products inside.