IF A DATA IS MISSING JUST SHOW ME HOW ITS DONE

Name: Partner: Date: 9 Torques and Rotational Equilibrium Introduction ACT Torque is defined as a twisting action on a body around a pivot point due to an applied force F. Mathematically, the magnitude of the torque is expressed as where r is the distance between the pivot point and applied force (also called the lever arm) and 0 is the angle between the lever arm and the applied force. For the specific situations in this laboratory, 0 = 90 for all cases. An applied torque will cause a body to rotate clockwise or counterclockwise. The direction of rotation determines the sign of the torque, where clockwise rotation is a negative torque and counterclockwise rotation is a positive torque. Forces that act at the pivot point of a body will cause no rotation, because for this particular case r = 0. In many ways, torques are analogous to forces. For an object to be in translational equilibrium, the sum of all forces must be zero. Similarly, for an object in rotational equilibrium, the sum of all torques about any point of rotation must be zero. Pre-lab and Discussion Questions Pre-Lab Questions This part of the lab is to be completed prior to class. You MUST show it to your instructor upon arrival or else no credit will be given for this section. 1. What are some everyday examples in which you use torque to complete a task? [2 pts] 2. You open a door by pushing its hinges - is it easier to open the door if the handle is far from the hinges, or close to the hinges? [2 pts] 3. Which of the following produces the greatest torque? [3 pts] (a) Small force, short lever arm (b) Large force, small lever arm c) Small force, long lever arm (d) Large force, long lever arm 714. COMPLETE THE SENTENCE: The same torque can be produced by a large force with short lever arm, or a small force with a ... [3 pts] Discussion Questions This part of the lab is to be completed with your group in class. 5. Can the same force produce different amounts of torque? Explain. [2 pts] 6. If you cannot exert enough torque to turn a stubborn bolt, would more torque be produced if you fastened a length of rope to the wrench handle as shown? Explain. [3 pts] 7. How do the torques of the two children on the seesaw compare? Explain. [5 pts] 1 3m-$1.5 m-/ 200 N 40ON 8. What is the weight of the block hung at the 10 cm mark? [5 pts] 20 40 60 BO 100 ? N 20 N 72Experiment In this laboratory, forces will be applied to a meter stick balanced on a pivot point. You will experimentally balance torques in a dynamic system. . Equipment: Meter stick, support stand, laboratory balance, hooked masses (200 g, 100 g, 50 g), 4 adjustable clamps (3 with hanger, 1 without) . Place the adjustable clamp without hanger on the meter stick and place it on the stand. Adjust the position of the clamp until the meter stick is balanced. The position of the clamp is now at the position of the center of gravity of the stick. Record this position as xCG in Data Table 1. . Measure the mass of each hooked mass and its clamp to the nearest gram (0.001 kg). Let m1 = 0.2 kg + mclampl, m2 = 0.1 kg + mclamp2, and m3 = 0.05 kg + mclamp3. Record these masses in Data Table 1. . Hang mi at the x1 = 0.30 m mark and hang m2 at the x2 = 0.65 m mark. . Experimentally determine the position x3 to the nearest mm at which mass my must be placed in order to balance the system. Record the value of x3 in Data Table 1. . Remove all masses and mass clamps from the meter stick. Data Table 1: Individual Torques [5 pts] xCG (m) = Mass (kg) Position (m) Lever arm (m) | Torque (Nm) m1 = 21 = 0.300 r1 = 71 = 2 = 2 = 0.650 12 = T2 = m3 = 3 = 13 = 73 = 1. Calculate the lever arm for each of the three masses and record them in Data Table 1. The lever arm is the positive distance from the position of each mass to the pivot point ("CG). Show the calculations below. [5 pts] 2. Calculate the torque caused by each mass and record in Data Table 1. Remember to use the proper sign convention for each torque. Show the calculations below. [5 pts] 733. Calculate the total clockwise and total counterclockwise torques and record them in Data Table 2. Sum to find the total torque and record in the last row to Data Table 2. Show the calculations below. [10 pts] Data Table 2: Total Torque [5 pts] ETCW (Nm): ETCCW (Nm): ET (Nm): 4. Does the data confirm that the system is in rotational equilibrium? Explain. [5 pts] 5. Assume that the ruler and meter stick clamp have a combined mass of 0.1 kg. Calculate the vertical force F exerted by the stand on the ruler with the three masses hanging from it in order to keep the system in translational equilibrium. Show your work. [10 pts] Application Question 6. In order to balance a meterstick at the 27 cm mark, how much weight would you need to hang at the 10 cm mark? Assume the stick weighs 200 g and its center of mass is at 50 cm. [10 pts] 74Results and Conclusions (20 pts) Briefly summarize the objective of today's lab as well as the results of your experiment. State any applicable errors you calculated and give AT LEAST two possible reasons your results deviated from theoretical values. If the experiment was purely qualitative (i.e. you did not calculate a % difference or % error), you may replace the two sources of error with two SPECIFIC concepts from lecture that the experiment demonstrated