Terminology
Term  Definition 
PF (Physics Fight)  Each unit of debating rounds. The main competition debates are referred to as the Selective PFs and the finals are referred to as the Final PFs. 
Round  Not an official IYPT terminology, but many use this term to refer to the individual PFs. In IYPT, selective PFs consist of five PFs, and each of these PFs a referred to as, for example, 1st Round, Round 1, or PF 1. 
Stage  One PF consists of 3 – 4 Stages. In each stage, each team is designated a role as a Reporter, Opponent, Reviewer, (and Observer) and these roles are circulated in the following Stages so that each team will have been each role once. 
SP (Sum of Points)  The sum of the points earned in each PF. The points system works in the following way:

TSP (Total Sum of Points)  The TSP of a team is their total sum of their SPs earned from each round. 
FW (Fights Won)  The number of times a team has placed 1st in a PF. Winning is dictated by the SP. 
Performing Roles
Reporter (Scoring Coefficient = 3.0)
The Reporter presents the essence of the solution to the problem, attracting the attention of the audience to the main physical ideas and conclusions.
Opponent (Scoring Coefficient = 2.0)
The Opponent asks questions to the Reporter, criticizes the report, and points out possible inaccuracies and errors in the understanding of the problem and the solution. The Opponent analyses the advantages and drawbacks of both the solution and the presentation of the Reporter. The discussion of the Opponent should not become a presentation of his/her own solution. In the discussion, the solution presented by the Reporter is discussed.
Reviewer (Scoring Coefficient = 1.0)
The Reviewer presents a short estimation of the presentations of the Reporter and Opponent.
Observer (Scoring Coefficient = 0.0)
The Observer does not participate actively in the PF.
During a PF, only one member of the team takes the floor as Reporter, Opponent or Reviewer; other members of the team are allowed to make brief remarks or to help with the presentation technically. No member of a team may take the floor more than twice during one Selective PF or, as Reporter, more than three times in total during all Selective PFs. In the Final PF, any team member can take the floor only once.
Stages of Physics Fights
Step  Stage  Procedure  Approximate Time Allocated (min) 
1  Opponent Challenges Reporter  The Opponent decides which questions that they would like to use to challenge the Reporter.  1 
2  Decision of Reporter  The Reporter decides either to accept or decline the challenge. If the challenge is declined, then Step 1 is repeated until a challenge is accepted.  1 
3  Preparation of Reporter  The Reporter prepares the presentation for the accepted question. This time slot includes setting up all necessary equipment.  5 
4  Presentation of Reporter  The Reporter delivers their presentation.  12 
5  Questioning of Reporter by Opponent  The Opponent may raise any questions that they have.  2 
6  Preparation of Opponent  The Opponent prepares for their presentation. This time slot includes setting up all necessary equipment  3 
7  Presentation of Opponent  The Opponent delivers their presentation. They may point out the advantages and drawbacks of both the solution and the presentation of the Reporter, as well as discussion questions that may be raised after the presentation.
The Opponent and the Reporter enter a discussion phase based on the discussion questions. If the Opponent decides not to present, then all 14 minutes can be used for discussion. 
14 
8  Summary  The Opponent summarizes the discussion.  1 
9  Questioning of Reporter by Opponent and Reviewer  The Opponent and especially the Reviewer may raise any questions that they have.  3 
10  Preparation of Reviewer  The Reviewer prepares for their presentation. This time slot includes setting up all necessary equipment.  2 
11  Presentation of Reviewer  The Reviewer delivers their presentation.  4 
12  Concluding Remarks of Reporter  The Reporter makes any final comments before closing the discussion.  2 
13  Questions of the Jury  The Jury may raise any questions that they have.  5 
Total Time: 55 min
Problem Challenge and Rejection
All problems presented in the same PF must be different.
The Opponent may challenge the Reporter on any problem with the exception for a problem that:
– was rejected by the Reporter earlier;
– was presented by the Reporter earlier;
– was opposed by the Opponent earlier;
– was presented by the Opponent earlier.
During the Selective PFs the Reporter may reject the challenge of one problem in total without penalty. For every subsequent rejection, the scoring coefficient of the Reporter is decreased by 0.2. This reduction continues to apply during the following selective PFs.
The following special rules apply to the last Selective PF:
– The procedure of challenge is omitted. All teams may choose any problem to present. The only exceptions are that a team may not present a problem which they have already presented earlier in the Selective Fights, and all problems presented in one group must be different. In case teams of one group choose the same problem, priority is given to the team with the higher TSP.
– A team has to select its problems and submit this selection before it leaves the competition room after the previous PF. This choice must be made public immediately.
– The problem which a team presents in this PF may not be presented again in the Final PF by the same team.
Within 4 hours after the announcement of the results of the Selective PF’s, the team participating in the Final PF may choose their problems. In case teams choose the same problem, priority of the problem selection is determined by the team with the highest TSP (in case of equality, by FW). This choice should be made public immediately. For the last and final selective fights, if a team does not select the problem according to the regulations, the problems will be selected randomly according to the regulations.
Grading
After each stage, the Jury grades the teams, taking into account of all presentations of the members of each team, the questions and answers to the questions, and their participation in the discussion. Each Jury member shows integer marks from 1 to 10. The mean of the highest and the lowest marks is counted as an individual mark, which is then added to the remaining marks. This sum is used to calculate the mean mark for the team. The mean marks for each team are then multiplied by their respective scoring coefficient.
Resulting Parameters
For a team in a PF:
The sum of points (SP) is the sum of mean marks, multiplied by the corresponding coefficients and rounded to one decimal.
For a team in the tournament:
The total sum of points (TSP) equals the total of the SP of the team in all selective PFs. The number of fights won (FW) is the number of selective PFs in which the team received the highest SP from all three or four teams participating in the same PFs.