Key terms & definitions

A relationship in which multiplying one quantity by a factor divides the other by that factor.

The operation used to find an angle from its sine value, written $\sin^{-1}$.

The relationship in which light intensity from a point source is proportional to the reciprocal of the square of its distance from the source.

Higher Tier: a relationship in which a quantity is proportional to the reciprocal of distance squared. For light intensity, $I \propto 1/d^2$.

The reciprocal of the time taken, written $1/t$. It is proportional to reaction rate when the same amount of change is timed.

A calculator operation that finds an angle from its sine or cosine, such as $A=\cos^{-1}(0.6)$.

A change from the usual word order, often used to emphasise a particular word or idea.

Describes an image that is upside down compared with its object.

A theory proposing that performance improves as arousal increases towards an optimal level, then declines as arousal increases further.

Finding relevant information about a designer, company or product through research and examination.

Research into an issue to uncover and report information that may be hidden, including evidence of wrongdoing.

Police work aimed at discovering what happened in a crime and identifying the offender by collecting and checking evidence.

The formal conferring of a Church office through presentation of its emblems. Lay investiture meant a secular ruler performing this act.

The conflict between the papacy and secular rulers over authority to appoint and install church officials, particularly bishops.

Money committed to a commercial activity, such as a trading voyage, in the expectation of receiving a financial return.

Spending money on businesses, equipment or infrastructure to increase production, income or future opportunities.

Money spent on an asset or project in the expectation of generating future benefits, such as additional profit.

A person who provides money for a project in the hope of gaining a financial return.

Protection against violation or attack, applied particularly to the persons of the plebeian tribunes.

Crime that is difficult to see or recognise and may therefore remain undetected, unreported or unrecorded, such as concealed workplace fraud.

Stitching arranged so that it is concealed or barely visible on the outside of a textile product.

Unemployment concealed by excluding people from official statistics, rather than finding them paid work.

Fertilising an egg with sperm outside the body, in a laboratory, before transferring an embryo into the womb.

A fertility treatment in which eggs are fertilised by sperm in a laboratory before one or two embryos are inserted into the uterus.

An appeal to a divine power for help or inspiration; an epic poet may invoke a Muse to assist the telling of the story.

Something that happens without conscious control.

An automatic action that does not require conscious thought, such as the normal control of heart rate.

Muscle that works without conscious control; in blood vessel walls, smooth muscle helps regulate blood flow.

Poverty experienced by someone living in a household where at least one person is in paid employment.

A mineral needed to make thyroid hormones, including thyroxine, which help regulate metabolic rate.