In light of an increased role for conceptual understanding of science in English primary schools, the research reported here investigated the views of force and gravity held by 20 primary teachers, using the 'interview about instances' technique. Results are reported in sections dealing with definitions of force; gravity and weight; views of friction; combinations of forces and the concept of a resultant force; reaction forces; force and motion; and finally, the teachers' use of scientific language. Nearly all of the teachers had views of these concepts that were not in accord with generally accepted scientific interpretations-most held views similar to those of children reported by other researchers. Some implications of the findings are discussed.

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The calculation of loads for floating offshore wind turbines requires time‐domain integrated simulation tools where most of the physical concepts involved in the system dynamics are considered. The loads at the different components are used for the structural calculation and influence the design noticeably. This study quantifies the influence of mooring dynamic models on the calculation of fatigue and ultimate loads with integrated tools and compares its performance with a lower computational cost quasi‐static mooring model. Three platforms representing the principal topologies (spar, semisubmersible and tension‐leg platform) were assumed to be installed at the same 200 m depth location in the Irish coast. For each platform, the fatigue and ultimate loads were computed with an integrated floating wind turbine simulation code using both, a quasi‐static and a fully dynamic moorings model. More than 3500 simulations for each platform and mooring model were launched and post‐processed according to the IEC 61400‐3 guideline in an exercise similar to what a certification entity may require to an offshore wind turbine designer. The results showed that the impact of mooring dynamics in both fatigue and ultimate loads increases as elements located closer to the platform are evaluated; the blade and the shaft loads are only slightly modified by the mooring dynamics in all the platform designs; the tower base loads can be significantly affected depending on the platform concept; and the mooring lines tensions strongly depend on the lines dynamics, both in fatigue and extreme loads for all the platform concepts evaluated. Copyright © 2016 John Wiley & Sons, Ltd.

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