Lab 07 Bell Crank Lever Experiment Lab Location Statics and Dynamics Laboratory Lab Objectives To compare...

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Lab 07 Bell Crank Lever Experiment Lab Location Statics and Dynamics Laboratory Lab Objectives To compare the experimental torque and the calculated torque using the Bell Crank Lever. 1. Lever and Torque M Line of application I F 90 Page 26 of 39 = Torque Force * Lever Length M=F*I where, M = Torque, F = Force, I Torque, F Force, I = Effective lever length Lever Principle Equilibrium prevails on the lever when the sum of counter-clockwise moments is equal to the sum of clockwise moments for the two examples below. |1 12 F1 F2 M2 M1 12 F1 F2 11 M1 M2 BMM1511 Engineering Mechanics Lab 1Vesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 2. Equipment and Components 1. TM 120 Bell crank lever. 2. Weight blocks (10N and 20N). 3. Experiment Procedure 1 2 3 7 or 8 Page 27 of 39 Figure 1: Bell Crank Lever Apparatus 11 F1 M1 O M2 12 F2 5 6 Figure 2: Parts of Bell Crank Lever Apparatus 1. Place the bell crank lever apparatus on a flat, horizontal bench. 2. Push the slider (1) to the desired lever length and secure it in position with the knurled screw (2). 3. Return the angle lever to equilibrium with the balance weight (3); the pin of the read-off point (5) must be positioned in the center of the hole. 4. Set the scale ring (7) of the load cell (8) to "zero". BMM1511 Engineering Mechanics Lab 1Vesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 4. Page 28 of 39 5. Place the desired weight of (8,11,14,17 & 20 N) on the pendulum. 6. Adjust the measuring device with the adjuster screw (6) so that the pin (5) is again positioned in the centre of the hole. 7. Read and note down the displayed value on the load cell (8) 8. Conduct the experiment with l at 200, 250, 300, 350 and 400mm. 9. Tabulate the experimental and calculated force F2. 10. Show a sample calculation. Discussions 1. Calculate the percentage errors and discuss any improvement can be made to reduce the errors. 2. Why is equilibrium important in statics and dynamics. 3. Why do you need to place the equipment on a flat, horizontal bench to perform the experiment? 4. Referring to the given figure below, simplify the horizontal arm force to equivalent system and calculate the value of F2 if F = 5.0 kN, I = 500mm, I2 = 300mm.Illustrate your answer with a free body diagram. 1 F1 M1 M2 12 F2 6. Give three(3) examples of the application of this experiment. BMM1511 Engineering Mechanics Lab IVesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 Experimental Data for Lab 7: Bell Crank Lever Experiment Weight/Load, F1 (N) 8 11 14 17 20 Value F1 Length, L1 (mm) 200 8 12 15 18 21 250 11 15 19 23 26 300 13 17 22 27 31 Value F2 350 15 20 26 31 36 400 17 23 29 35 41 Student has to calculate theoretical value for F2 using equation: M1 = M2 F1 x L1 = F2 x L2 Lab 07 Bell Crank Lever Experiment Lab Location Statics and Dynamics Laboratory Lab Objectives To compare the experimental torque and the calculated torque using the Bell Crank Lever. 1. Lever and Torque M Line of application I F 90 Page 26 of 39 = Torque Force * Lever Length M=F*I where, M = Torque, F = Force, I Torque, F Force, I = Effective lever length Lever Principle Equilibrium prevails on the lever when the sum of counter-clockwise moments is equal to the sum of clockwise moments for the two examples below. |1 12 F1 F2 M2 M1 12 F1 F2 11 M1 M2 BMM1511 Engineering Mechanics Lab 1Vesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 2. Equipment and Components 1. TM 120 Bell crank lever. 2. Weight blocks (10N and 20N). 3. Experiment Procedure 1 2 3 7 or 8 Page 27 of 39 Figure 1: Bell Crank Lever Apparatus 11 F1 M1 O M2 12 F2 5 6 Figure 2: Parts of Bell Crank Lever Apparatus 1. Place the bell crank lever apparatus on a flat, horizontal bench. 2. Push the slider (1) to the desired lever length and secure it in position with the knurled screw (2). 3. Return the angle lever to equilibrium with the balance weight (3); the pin of the read-off point (5) must be positioned in the center of the hole. 4. Set the scale ring (7) of the load cell (8) to "zero". BMM1511 Engineering Mechanics Lab 1Vesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 4. Page 28 of 39 5. Place the desired weight of (8,11,14,17 & 20 N) on the pendulum. 6. Adjust the measuring device with the adjuster screw (6) so that the pin (5) is again positioned in the centre of the hole. 7. Read and note down the displayed value on the load cell (8) 8. Conduct the experiment with l at 200, 250, 300, 350 and 400mm. 9. Tabulate the experimental and calculated force F2. 10. Show a sample calculation. Discussions 1. Calculate the percentage errors and discuss any improvement can be made to reduce the errors. 2. Why is equilibrium important in statics and dynamics. 3. Why do you need to place the equipment on a flat, horizontal bench to perform the experiment? 4. Referring to the given figure below, simplify the horizontal arm force to equivalent system and calculate the value of F2 if F = 5.0 kN, I = 500mm, I2 = 300mm.Illustrate your answer with a free body diagram. 1 F1 M1 M2 12 F2 6. Give three(3) examples of the application of this experiment. BMM1511 Engineering Mechanics Lab IVesion 1 (Nurhani & Lee) Implementation Date: 01-09-2012 Experimental Data for Lab 7: Bell Crank Lever Experiment Weight/Load, F1 (N) 8 11 14 17 20 Value F1 Length, L1 (mm) 200 8 12 15 18 21 250 11 15 19 23 26 300 13 17 22 27 31 Value F2 350 15 20 26 31 36 400 17 23 29 35 41 Student has to calculate theoretical value for F2 using equation: M1 = M2 F1 x L1 = F2 x L2