A student wants to find out the coefficients of static friction and kinetic friction among a box and a plank. She puts the box on the plank and steadily increases one end of the plank. If the angle of inclination with the horizontal reaches 40°, the box begins to slip and it slides 2.4 m down the plank in 4.5 s at constant acceleration.
Determine the coefficient of static friction?
Determine the coefficient of kinetic friction?