A firework is launched vertically from the ground. When the firework reaches a height of 360m, the firework explodes, producing coloured light. A student on the ground below the firework incorrectly measures the time between seeing the coloured light and hearing the explosion. The student obtains a value of 1.8 s. What is the speed of sound that the student's value suggests?

Below are four statements about the uses of electromagnetic radiation. Gamma rays are used in medical treatment. Infr…

A ripple tank is used to show wave behaviour. The dipper vibrates up and down at a constant frequency. What happens t…

A wave has a frequency of 10 kHz. Which pair of values of its speed and wavelength is possible?

One kilowatt-hour of energy costs $0.24. How much does it cost to run a 2 kW heater for three hours?

A single electrical component is placed inside a box. Two leads from the component emerge from the box. These leads a…

A beam of alpha-particles enters the magnetic field between the poles of a magnet. In which direction is the magnetic…