Question

Cart on an Incline plane. Start up the Dynamics Track apparatus. Set the µKS? # stepper to zero (µk = 0.12 and µs = 0.18 by default). Please notice that the dynamic track has a feature to be tilted by dragging when the mouse cursor is in the colored part of either end of the track. The message box informs that the track can be tilted up or down. With the brake off, turn on the friction pad and put extra 400 grams mass on the cart. Remove the string and attached hanger from the set up used in the part 1a. The string, pulley and hanger are not needed for this part of the experiment. The free body diagram for an object on an incline plane is given in Figure. 3. Keep the Dynamic Vectors ON, by clicking on the vectors’ box located above the masses, to see the forces acting on the cart. Now start increasing the incline angle θ by small increments (the static friction force will increase as well as can be seen on the force diagram), until you reach some critical angle θc when the cart starts sliding downhill. Repeat the experiment to read a more accurate value for θc. At that angle the static friction force has reached its maximum value. Use formula (4) to calculate the coefficient of static friction. Compare your calculated value with the given one (which is given in the control box for µS (0.18)) by calculating the discrepancy: 100%* (|calc. value– expect. value| / expect. value).

1b) Cart on an inclined plane

Trial	Critical angle (Θ)
1	10.3 °
2	10.3 °
3	10.3°

1b) Cart on an Incline plane

The experimental value of the coefficient of static friction µ_s is calculated with equation (4) as follows:

(Show equation and calculation)

Determine the discrepancy between the above-calculated value and the given one to compare them: 100%* (|calc. value– expect. value| / expect. value).

(Show equation and calculation)

Answer 1

Ms N for jst taut to slide andc