Group R

In relation to motorsport governed by the Fédération Internationale de l'Automobile, Group R refers to a set of regulations providing production-derived vehicles for outright competition. The Group R regulations were created in 2012 as a replacement for Group A and Group N cars, and took effect from 2013. No new cars will be homologated under Group A or Group N regulations, and instead existing cars are reclassified according to Group R rules. As part of its structure, the Group R regulations have a provision for GT cars, known as RGT.

Classes under Group R

Group R consists of six classes, designated R1, R2, R3, R4, R5, R6 and RGT; some of these groups will contain their own sub-groups, with cars allocated to each group based on their weight, engine size and powertrain. Teams and drivers are sorted into a specific championship based on the class their car fits into. Cars classified as R1, R2 and R3 contest the World Rally Championship-3 for two-wheel drive cars; specially-prepared R3T cars are also used in the Junior World Rally Championship. Cars classified as R4 and R5 compete in the World Rally Championship-2 alongside existing Super 2000 and Group N Production Cars. Cars classified as RGT compete in the R-GT Cup.

Group

Group may refer to:

Groups of people

In science and technology

In mathematics

In chemistry

In computing and the internet

Other uses in science and technology

Other uses

Shot grouping

In shooting, a shot grouping, or simply grouping, is the placement of multiple shots on a target, the shots taken in one shooting session. The closeness of the grouping, the nearness of all the shots to each other, is a measure of the accuracy of a weapon, and a measure of the shooter's consistency and skill.

Uses of the term

For firearms that shoot one round at a time, a shot grouping can be used to measure the accuracy of the system comprised out of weapon as well as the precision and uniformity of the ammunition by fixing the weapon into position on a test mount, and aiming it at a target. Multiple shots using rounds from same type and batch are fired to observe how the weapon groups the shots. If a person holds the weapon and shoots it, the grouping measures the combination of the person's skill and the weapon's accuracy.

In shotgun shooting, the grouping is also called the pattern. The pattern is the spread of shot from a single shotgun shell, measured as the smallest circle containing all the shots on the target. The barrel of a shotgun is designed to deliver a wide or narrow grouping, depending on the expected use. Shooting at close range indicates a cylinder bore barrel to deliver a wide grouping, while for hunting at longer distances such as 50 yards or meters, a choke is recommended for a tighter grouping.

Stratigraphic unit

A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features (facies) that characterize it.

Units must be mappable and distinct from one another, but the contact need not be particularly distinct. For instance, a unit may be defined by terms such as "when the sandstone component exceeds 75%".

Lithostratigraphic units

Sequences of sedimentary and volcanic rocks are subdivided on the basis of their lithology. Going from smaller to larger in scale, the main units recognised are Bed, Member, Formation, Group and Supergroup.

Bed

A bed is a lithologically distinct layer within a member or formation and is the smallest recognisable stratigraphic unit. These are not normally named, but may be in the case of a marker horizon.

Member

A member is a named lithologically distinct part of a formation. Not all formations are subdivided in this way and even where they are recognized, they may only form part of the formation.