2.1 The first particle accelerator was built in 1930 by Cockcroft and Walton.
5.2 The quark content of the neutron is $udd$.
This solutions manual provides a comprehensive guide to the exercises and problems in "Introduction to Elementary Particles" by Griffiths. The solutions are presented in a clear and concise manner, making it an invaluable resource for students and researchers alike.
5.1 The quark content of the proton is $uud$.
7.1 The weak interaction is responsible for $\beta$ decay.