Projectile motion is usually the first non-uniform two-dimensional motion that students will encounter in a pre-university physics course. In this article, we introduce a novel technique for capturing the trajectory of projectile motion on an inclined Perspex plane. This is achieved by coating the Perspex with a thin layer of fine water droplets that allows the projectile to leave a trail as it passes. The experiment was field-tested in Singapore and the response was very good.

Feedback on part I of this series (Ho et al 2009 Phys. Educ. 44 253) motivated us to make hitting the target more interesting with a simple innovation: changing the target to a ring shaped hoop or goalpost and shooting for it in the 'air', as if playing basketball on the inclined plane. We discuss in detail the demarcation of the boundary (safety parabola) between the accessible region and the inaccessible region for a projectile on the surface of the inclined plane, and derive the angle of projection for scoring a goal. We also consider the orientation of the rings for maximizing the chance of scoring.

The λφ4 model is conventionally used to explain the origin of mass of elementary particles through the Spontaneous Symmetry Breaking (SSB) phenomena. The triviality status of the λφ4 model in 4-dimensional spacetime remains an open question despite attempts by several authors. This study establishes a new approach to determine the triviality status of the λφ4 model based on an unpublished note by Professor Bryce DeWitt. We adopted the DeWitt's Ansatz for the 2-point connected correlation function on the lattice [Formula: see text] where α is a parameter that measures the departure from triviality. Calling α's continuum counterpart as β, then a non-zero value of β signifies non-triviality of the λφ4 model. The 2-point connected correlation function, given in terms of an Euclidean functional integral, is computed numerically via Monte Carlo methods. Our analysis, based on β, is different from the traditional analysis based on the renormalized coupling constant λR. To test the new approach, we performed the simulation in 2 dimensions and obtained results that are consistent with previous findings: 2-dimensional λφ4 model is non-trivial. Finally, for the case in 4 dimensions, our results show that the model is non-trivial.