# Objects mass kg force of gravity n f g m98 ms 2

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Object(s) Mass (kg) Force of Gravity (N) F g =m(9.8 m/s 2 ) Normal Force (N) Cancels gravity in this situation so same value as F g Static Friction Force (N) 1 box Man Girl + 1 Box Trash can
Man + 1 box Box + trashcan Man + trashcan Refrigerator IF THE OBJECT DOES NOT MOVE EVEN WITH 500 N of force, place an X through the data as it means we cannot find the static friction’s maximum value. Use the data to construct a Static Friction vs. Normal Force. Title your graph Static Friction vs. Normal Force Label your x-axis F N with units N ; our independent variable (x) will be Normal Force. o This should be a positive number, and the same magnitude (size or number) as the Force of Gravity Label your y-axis F sf with units N ; our dependent variable (y) will be the Static Friction Force o Ignore direction for this graph, all values should be positive values. Draw a line of best fit using the points Record the m (slope) and b (y-int) value Write your y=mx+b equation: ________________________________ The slope here represents our coefficient of friction (µ s ) which you can think of as a measure of the stickiness between two surfaces. It is a measure of the ratio of friction and normal force. The subscript ‘s’ next to the µ indicates we are talking about static friction and an object not in motion. We can specify it as the formula below. F sf = µ s (F N ) Static Friction = coefficient of static friction x Normal Force Your slope (m value) in the graph is the coefficient. Write it down: µ s = _______________ 1. Using your coefficient from the graph (slope), multiply it by the normal force for the box (490 N). What do you get? Show your work.
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