1. How can you determine a coefficient of friction with only acceleration as a given variable ? I have a problem with a book resting on a box. Both are moving at an acceleration of 3.5 m/s^2 and I need to find the smallest coefficient of static friction that will prevent slippage. 2. Will a force applied on top of a box sitting on an inclined ramp make it move? (the force is perpendicular to the ramp) Thanks.