1011 past contests
Topic 41 · Distance from a long straight wire for a given magnetic flux density, given b at one distance
Topic 2 · Escape velocity, radius and surface gravity relationships for celestial bodies
Topic 41 · Magnetic flux density at a new distance from a long straight wire, given b at one distance
Topic 19 · Types of radioactive decay: beta, alpha and gamma, and their nuclear changes
Topic 15 · Riddle: the semiconductor, an insulator only at absolute zero
Topic 46 · Focal length of a thin plano-convex lens from its radius and refractive index (three variants)
Topic 21 · Angular momentum of an electron in the bohr model's n=2 hydrogen orbit
Topic 28 · Ratio of black-body power output after a temperature decrease and area increase
Topic 61 · Potential energy of a displaced pendulum from its length, mass and a smaller angle
Topic 28 · Ratio of black-body power output after simultaneous temperature decrease and area increase
Topic 61 · Pendulum potential energy at a new angle, scaled from a known angle's potential energy
Topic 61 · Potential energy of a displaced pendulum from its length, mass and angle
Topic 42 · Power factor of a series r-x circuit from resistance and reactance (three variants)
Topic 28 · Ratio of black-body power output after simultaneous temperature and area changes
Topic 62 · Riddle: ultrasound as a longitudinal mechanical wave beyond human hearing
Topic 64 · Wavelength from speed and frequency (true/false)
Topic 64 · Wave speed from frequency and wavelength (true/false, mismatched value)
Topic 64 · Wave speed from frequency and wavelength (true/false)
Topic 58 · Resistor colour codes: red-red-red, black-red-red and black-black-red, none of which denote 22 ω (true/false)