# Physics Essay

820 Words4 Pages
Purpose: the purpose of this experiment is to investigate the two different conditions necessary to reach equilibrium in an object. These two conditions are that the net force must add up to zero and the torque should add up to zero as well. Equipment: Knife edge clamps, Balance support, Meter stick and Masses. Method: we started by balancing a meter stick on the balance support. Next we used 2 masses one on each side to balance the masses 3 times at different distances form the center. Next we used 3 masses and placing two at different distances form the center on one side of the meter stick from the center. We performed this 3 times as well. In order for the torque to equal zero and the meter stick to be balanced, the total force times the total distance from the center has to be equal on both sides of the meter stick. Results: M= .507 kg F1 = m1g (N) D1 (m) t = F1d1 (Nm) F2 = m2g (N) d2 (m) Τ2 = F2d2 (Nm) Percent Difference 0.4905 .415 .204 .981 .21 .206 .9% 0.4905 .40 .196 1.962 .10 .196 0% 0.981 .20 .196 1.962 .10 .196 0% F1 = m1g (N) D1 (m) t = F1d1 (Nm) F2 = m2g (N) d2 (m) F3 (m) D3 (m) Τ2 = F2d2 + F3d3 (Nm) Percent Difference 1.962 .1225 .240 .4905 .11 1.962 .20 .392 .4905 .22 1.962 .30 .589 .4905 .351 Questions: 1. At the beginning of each experimental run, the velocities of both the cart and the hanging mass were zero. a. What was the kinetic energy of the cart? 0J b. What was the kinetic energy of the hanging mass? 0J 2. Consider the first measurement that you made with only 25 grams attached to the string. a. What was the velocity of the cart after it moved a distance h? .71 m/s b. When the cart/hanging mass system was moving with this velocity, what was the kinetic energy of the cart? .128 J c. What was the kinetic energy of the hanging mass (hanger plus attached mass)? .006 J