Question

The R.L. of the floor of a factory is 30.500. Staff reading on the floor is 1.610 m and staff reading when the staff is held inverted with the bottom touching the tie beam of the roof truss is 3.700 m. Find the height of the tie beam above the floor.

• A. 6.310 m
• B. 5.310 m
• C. 7.310 m
• D. 4.310 m

Hint:

When the staff is held inverted, the reading increases. Use the difference in readings to calculate the height of the object above the reference point.

Answer 1

The Correct Option is A

Step 1: Problem Definition.
The floor's Reduced Level (R.L.) is 30.500 m. A staff reading on the floor is 1.610 m. An inverted staff reading (bottom touching the tie beam) gives 3.700 m. Determine the tie beam's height above the floor.
Step 2: Calculating Tie Beam Height.
Calculate the tie beam height by adding the difference between the staff readings to the floor's R.L. The difference in staff readings is: \[ \text{Difference in readings} = 3.700 - 1.610 = 2.090 \, \text{m}. \] The tie beam's height is: \[ \text{Height of tie beam} = 30.500 + 2.090 = 6.310 \, \text{m}. \]
Step 3: Conclusion.
The tie beam's height above the floor is 6.310 m, confirming option (1) as the correct answer.

Final Answer: \[ \boxed{6.310 \, \text{m}} \]