Question

Consider a rectangular box barge of length 80 m, breadth 20 m and depth 15 m floating at an even draught of 10 m. Assume that the heave added mass of the vessel is equal to its mass displacement and the acceleration due to gravity is 9.81 m/s\(^2\). The heave natural period of the vessel lies in between ________________ s.

• A. 1 and 5
• B. 6 and 10
• C. 11 and 15
• D. 16 and 20

Hint:

To calculate the heave natural period of a barge, use the vessel's length and displacement in the formula. A larger vessel typically has a longer period.

Answer 1

The Correct Option is B

Step 1: Heave natural period of a vessel.
The heave natural period is related to the vessel’s length and displacement. The period can be estimated using formulas derived from the vessel's geometry and mass.
Step 2: Analyze the given data.
The dimensions and draught are provided, and we assume the added mass is equal to the vessel's mass displacement. Using formulas for the natural period of a box-shaped barge, we can calculate an expected period.
Step 3: Conclusion.
The calculated natural period for the given parameters lies between 6 and 10 seconds, making option (B) the correct answer. Thus, the correct answer is (B).