REWRITE THIS PROCEDURE IN OWN WORDS

Procedure

1.Set clamp A on the boom to approximately the 40 cm position.Weigh the boom (including the clamp and pin) on the triple-beambalance. Record this weight in gwt on the data sheet as w. Balancethe boom on a finger and locate its center of gravity. Mark thecenter of gravity with a pencil, and erase any other markings onthe boom

.2.Assemble the crane approximately as shown in Figure 1. A loadof 700 to 1200 g should be applied to the weight holder. One end ofthe spring balance should be directly attached to the hook on clampC on the vertical pole. The other end of the spring balance shouldbe attached through a string or loop of string to clamp A on theboom. The top of the weight hanger should be below the lower end ofthe boom. Adjust clamp C until the string between the balance andthe boom is accurately horizontal. Hold a plumb line near thatstring and look for an equality of the four right angles. The boomshould make an angle of between 30o and 60o with the horizontal. Ifit does not, change the length of string between the balance andclamp A on the boom; then readjust clamp C on the vertical poleuntil that string is again horizontal.

3.Record the load force L in gwt. Remember to include the weightof the weight hanger along with that of the slotted weights.

4.Momentarily release the tension applied to the spring balanceby tilting the boom slightly while supporting the balance in itsoriginal position with one hand. Take a zero reading to be used forcorrecting future readings and record the zero reading of thebalance on scratch paper; or alternately adjust the balance untilit reads zero. Release the boom; and then pull down on it slightlyto slightly increase the reading of the balance. Next, slowlyrelease the force applied to the boom and remove your hands fromthe apparatus. This procedure will cause the frictional forceinside the spring balance to have the same direction when the finalreading is taken as when the zero reading was taken. Read the forceSmeas from the balance and make any required zero corrections onthe reading before recording it on the data sheet.the force Smeasfrom the balance and make any required zero corrections on thereading before recording it on the data sheet.