Topic 02Physics (Edexcel)

Materials

Materials — Edexcel International A-Level Physics (Unit 1). Covers: Density and Fluids; Hooke's Law, Stress and Strain.

1

Density and FluidsSign up

be able to use the equation density rho = m/V · understand how to use the relationship upthrust = weight of fluid displaced · (a) be able to use the equation for viscous drag (Stokes' Law), F = 6 pi eta r v. (b) understand that this equation applies only to small spherical objects moving at low speeds with laminar flow (or in the absence of turbulent flow) and that viscosity is temperature dependent · CORE PRACTICAL 2: Use a falling-ball method to determine the viscosity of a liquid

40 min
2

Hooke's Law, Stress and StrainSign up

be able to use the Hooke's law equation, F = k x, where k is the stiffness of the object · understand how to use the relationships (tensile or compressive) stress = force/cross-sectional area; (tensile or compressive) strain = change in length/original length; Young modulus = stress/strain. · (a) be able to draw and interpret force-extension and force-compression graphs. (b) understand the terms limit of proportionality, elastic limit, yield point, elastic deformation and plastic deformation and be able to apply them to these graphs · be able to draw and interpret tensile or compressive stress-strain graphs, and understand the term breaking stress · CORE PRACTICAL 3: Determine the Young modulus of a material · be able to calculate the elastic strain energy Eel in a deformed material sample, using the equation Eel = 1/2 F x, and from the area under the force-extension graph. The estimation of area and hence energy change for both linear and non-linear force-extension graphs is expected.

40 min