Chapter 1, Problem 1P

In a lab frame of reference, an observer finds Newton’s second law is valid in the form ${\displaystyle \underset{\begin{array}{l}\text{actual}\\ \text{physical}\\ \text{forces}\end{array}}{\sum }F=ma}$. Show that Newton’s second law is not valid in a reference frame moving past the laboratory frame of Problem 1 with a constant acceleration a₁. Assume that mass is an invariant quantity and is constant in time.