State what is meant by an inertial frame of reference.
A pair of detectors is set up to measure the intensity of a parallel beam of unstable particles. In the reference frame of the laboratory, the detectors are separated by a distance of 90 m. The speed of the particles in the beam is 0.80c0.80c0.80c.
The intensity of the beam at the second detector is 6.25% of the intensity at the first detector.
Calculate the half-life of the particles in the reference frame in which they are at rest.
In calculations involving time dilation, it is important to identify proper time. Identify the proper time in the calculation in Part 2.
22 exam-style questions on AQA A Level Physics Special relativity (A-level only), covering The Michelson-Morley experiment (A-level only), Einstein's theory of special relativity (A-level only), Time dilation (A-level only), Length contraction (A-level only), and Mass and energy (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.