1. The problem statement, all variables and given/known data Two identical vehicles 1 vehicle stationary and with brakes applied other vehicle travelling at 15mph. Road surface of good tarmacadam but damp after rain. Would occupants of both vehicle experience the same forces and would the injuries sustained be equal? 2. Relevant equations Newtons laws of motion 3. The attempt at a solution So long ago since I worked this at out college (50 years!) I can't remember formulae and method. Any help would be appreciated.