Strength Lab
Materials * Helical spring * support * rods * weight hanger * slotted masses * vertical scale * stopwatch.
Procedure
Part I: Determination of k from Hooke's Law 1. Suspend the spring from its support. 2. Hook the weight hanger from the bottom loop of the spring and determine the vertical scale reading of the bottom of the weight hanger. 3. Record this as the equilibrium position of the system. 4. Add 5 g to the weight hanger and again record the actual vertical scale reading. 5. Repeat this procedure for 10, 15, and 20 g added to the weight hanger. 6. To determine the force, F, needed to displace the spring, measure each of the slotted masses, individually, then convert the sum of the added masses to a weight in dynes (see lab manual for conversion). 7. The extension of the spring, x, is found by subtracting the vertical scale reading in each case from the equilibrium position reading. 8. Plot a graph with the added weight, F, on the vertical axis and the extension, x, on the horizontal axis, using the last two columns of the table on your Report Sheet. Draw a straight line, which best represents your data and properly label the graph.
4.1 Measure the required dimensions of the Helical spring before testing.
4.2 For tension, fix up the Helical spring with the help of upper and lower hooks.
For compression, keep the Helical spring in between the plates.
4.3 Fix the pointer of load dial and deflection scale at zero position.
4.4 Start the pump, keeping the release valve closed and gradually open the load valve to apply load on the spring.
4.5 Note the deflections at three different loading positions.
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1.AIM: Determination of Stiffness and modulus of rigidity of a close-coiled Helical spring. 2.EQUIMENTS:
2.1. Spring testing machine.
2.2. Micrometer.
2.3. Specimen.
2.4. Vernier caliper.
Procedure
Part I: Determination of k from Hooke's Law 1. Suspend the spring from its support. 2. Hook the weight hanger from the bottom loop of the spring and determine the vertical scale reading of the bottom of the weight hanger. 3. Record this as the equilibrium position of the system. 4. Add 5 g to the weight hanger and again record the actual vertical scale reading. 5. Repeat this procedure for 10, 15, and 20 g added to the weight hanger. 6. To determine the force, F, needed to displace the spring, measure each of the slotted masses, individually, then convert the sum of the added masses to a weight in dynes (see lab manual for conversion). 7. The extension of the spring, x, is found by subtracting the vertical scale reading in each case from the equilibrium position reading. 8. Plot a graph with the added weight, F, on the vertical axis and the extension, x, on the horizontal axis, using the last two columns of the table on your Report Sheet. Draw a straight line, which best represents your data and properly label the graph.
4.1 Measure the required dimensions of the Helical spring before testing.
4.2 For tension, fix up the Helical spring with the help of upper and lower hooks.
For compression, keep the Helical spring in between the plates.
4.3 Fix the pointer of load dial and deflection scale at zero position.
4.4 Start the pump, keeping the release valve closed and gradually open the load valve to apply load on the spring.
4.5 Note the deflections at three different loading positions.
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1.AIM: Determination of Stiffness and modulus of rigidity of a close-coiled Helical spring. 2.EQUIMENTS:
2.1. Spring testing machine.
2.2. Micrometer.
2.3. Specimen.
2.4. Vernier caliper.