Recall the equation of a line: of nonboral # ded y = mx + b 7x Where y is the dependent variable, x is the independent variable, m is the slope of the line and b is the y-intercept. Many equations we use in physics have this form. When we plot our data, it will not look exactly like a straight line but we can use tools like Excel to "fit" a line and calculate the slope and intercept. We will practice that in this lab. Pre-Lab Questions: 1) What is the "least count" for a meter stick? If you measured an object to be 15 cm, how would you write the length including the uncertainty? 2) If my measured value is 4.2 0.3 and the accepted value is 4.7, calculate the percent discrepancy. What is the percent uncertainty? 3) If your percent error is smaller than your percent discrepancy then your measurement is not a success. Or you have possibly uncovered new physics (probably not the case). Would you consider the measurement from question 2 to be a success? Why or why not? 4) Look at the equation x = vt where v is velocity, x is distance and t is time. Is there a linear relationship between distance and time? Which variables correspond to the dependent variable, the independent variable, and the slope of the line? 2