The data in the Table I were gathered using a force meter pulling horizontally on a block of wood placed on a level flat surface also made of wood. To increase the weight being pulled by the force meter, extra masses were added to the top of the block before each of the four trials. The diagram below shows the experimental set-up for the first part of this experiment, where the forward direction is to the right. The parameter being controlled in this experiment is the nature of the wooden surfaces. The variable being manipulated is the mass of the wood. The variables being measured are the forces of friction. The parameters being tested are the coefficients of friction. Wood surface Block of wood Two extra masses Force of friction drags String Force sensor Applied force The maximum static friction is defined as the largest recorded reading on the force sensor before the block starts moving; the kinetic friction is defined as the force, as measured on the force sensor, that causes the block to move at a constant velocity. Table I: Mass and Friction Data Total mass (kg) (wood block plus Maximum Fs (N) Fk FN = mg s (N) (N) masses on top) 0.50 1.96 1.47 1.0 3.92 2.94 1.5 5.88 4.41 2.0 7.84 5.88 k Treatment: Complete the table. Analysis: 1. Plot a graph of force of static friction vs normal force. Calculate the slope of this graph. 2. Plot a graph of force of kinetic friction vs normal force. Calculate the slope of this graph. Task 3: Technical Report: Answer the following in one sentence each. a) How does the mass of an object pulled along a horizontal surface affect the force of static friction? (Use the data table to help you answer this question) b) How does the mass of an object pulled along a horizontal surface affect the force of kinetic friction? (Use the data table to help you answer this question) c) How does the mass of an object pulled along a horizontal surface affect the coefficient of static friction? (Use the data table to help you answer this question) d) How does the mass of an object pulled along a horizontal surface affect the coefficient of kinetic friction? (Use the data table to help you answer this question) e) How do the slopes of the graphs relate to the coefficients of friction? Extension: What information is provided by the slope of the graph of force of kinetic friction vs normal force?