Abstract: The apparatus for determining coefficients of friction collects data required for determining static and dynamic coefficients of friction between various materials. The apparatus includes a ramp with adjustable slope and a plurality of test masses for placement on the ramp. Upslope lights and sensors, downslope lights and sensors, and a digital angle meter are installed on the ramp. The apparatus has a timing device having a display to show the elapsed time between a test mass passing the upslope sensor and the downslope sensor. The operator can determine the static coefficient of fraction from the tangent of the angle displayed on the digital angle meter when a test mass first begins to slide, and can compute the kinetic coefficient of friction from the angle displayed on the digital angle meter and the elapsed time shown on the timing device.

Abstract: The apparatus for determining coefficients of friction collects data required for determining static and dynamic coefficients of friction between various materials. The apparatus includes a ramp with adjustable slope and a plurality of test masses for placement on the ramp. Upslope lights and sensors, downslope lights and sensors, and a digital angle meter are installed on the ramp. The apparatus has a timing device having a display to show the elapsed time between a test mass passing the upslope sensor and the downslope sensor. The operator can determine the static coefficient of fraction from the tangent of the angle displayed on the digital angle meter when a test mass first begins to slide, and can compute the kinetic coefficient of friction from the angle displayed on the digital angle meter and the elapsed time shown on the timing device.