Experiment No.02 Verification of Lami's Theorem by using Universal Force Table

Описание: #Engg.Mechanics #lami'stheorem #concurrentforces #coplanerforces #forcesystem #sycet #shreeyashcollege #engineeringmechanics #experiment #practical #EMpractical

To verify the lami's theroem by using universal force table

The Law of Polygon of Forces states that “If any number of coplanar concurrent forces can be represented in magnitude and direction by the sides of a polygon taken in order, then their resultant will be represented by the closing side of the polygon taken in opposite order”.

If the forces form a closed polygon, then the system is in equilibrium. Figure 1.1 and Figure 1.2 shows a system of five forces 𝐹1,𝐹2,𝐹3,𝐹4 and 𝐹5. The forces are forming a closed polygon in the first figure, hence they are in equilibrium. In the second figure, the system is not in equilibrium, and the closing side, shown by dotted line, denotes the Resultant 𝑅 of the force system.

PROCEDURE:
1. Set up the apparatus provided after measuring and recording the weights of the pans.

2. Level the force table by adjusting the foot screws & check it with help of bubble tube.

3. Apply the forces P1, P2, P3, P4 & P5 so that the pivot remains at centre of ring. Note down the magnitude & direction of forces.

4. Observe the angles between consecutive forces & note it.
5. Draw space diagrams for each reading using Bow’s notation & then draw the force polygon with proper scale for all forces on graph paper.
Observe the nature of polygon whether it is open or closed.

7. Apply unknown weight on one of the strings & adjust the forces in other strings to so that the pivot remains at centre of ring.

8. Find the unknown weight by drawing space diagram & force polygon.

9. Repeat the above procedure by changing any one or two pulley positions and take three sets of observations.