1. MID-EXAM I Revision

2. Question 1
The floor causes couple moments MA and MB on the brushes of the polishing machine shown below. MA = 40 N⋅m , MB = 30 N⋅m and the distance a=0.3 m. Determine the following:
The magnitude of the couple forces that must be developed by the operator on the Handles so that the resultant of the moment is zero.
The magnitude of the couple forces if the brush at B suddenly stops so that MB =0?

4. Question 2
A 40-N horizontal force is applied to the end of a lever shown in figure below . Determine the moment around point A.

6. Question 3
A three forces shown in figure below. Determine the magnitude of the resultant of these forces and its direction measured clock wise from x-axis.

7. Question 4
determine the reactions at the supports A and C, also compute the internal force in members EF, ED AF and AE using joint method of analysis. Indicate whether the members are in tension or in compression.

9. Question 5
The mass m = 120 kg as shown below. Determine the force in members BD, CD, and CE, and state if the members are in tension or compression.

11. Question 6
For the beam shown below . Determine the reactions at supports B and E