**aberration and Doppler effect, mass-energy relation, simple applications to a decay process; Four dimensional momentum vector; Covariance of equations of physics.**

Questions:

**Q 1.** A meson of rest mass $\pi$ comes to rest and disintegrates into a muon of rest mass $\mu$* *and a neutrino of zero rest mass. Show that the kinetic energy of motion of the muon is **$T=\frac{(\pi -\mu)^2c^2}{2\pi}$****. [10 marks]**

**Q 2.** A motorist goes through a red light and, when challenged, claims that colour
he actually saw was green and not red because of the Doppler effect. What should
be his speed for his claim to be true? **[15 marks]
**

Video Solution at 11 pm