1. What is the Weight Calculator?

Definition: The Weight Calculator determines the weight (\(W\)) of a steel bar using the formula \(W = \frac{\gamma \pi d^2 L}{4}\), where \(\gamma = \rho g\), converting the result to Newtons (N), kilograms (kg), and pounds (lb).

Purpose: Assists engineers in calculating the weight of steel bars based on density and dimensions.

Reference:Applied Strength of Materials for Engineering Technology

http://www.etcs.pfw.edu/~dupenb/ET_200/Applied%20Str%20of%20Mat%20for%20ET%20v14%20July%202018.pdf

2. How Does the Calculator Work?

Formula:

Where:

• \(W\): Weight (N, kg, lb)
• \(\gamma\): Specific weight (\(\rho g\), N/m³)
• \(\rho\): Density (kg/m³)
• \(g\): Gravity (m/s²)
• \(d\): Diameter (m)
• \(L\): Length (m)

Steps:

• Step 1: Input Density. Enter the density (e.g., 7.85 g/cm³).
• Step 2: Input Diameter. Enter the diameter (e.g., 5 cm or 2 in).
• Step 3: Input Length. Enter the length (e.g., 2 m or 6 ft).
• Step 4: Input Gravity. Enter gravity (e.g., 9.81 m/s²).
• Step 5: Calculate. The calculator computes weight in N, kg, and lb.

3. Importance of Weight Calculation

Calculating weight is crucial for:

• Material Selection: Ensures steel components meet weight requirements.
• Design Safety: Prevents overloading due to excessive weight.

4. Using the Calculator

Example: Density = 7.85 g/cm³, Diameter = 5 cm, Length = 2 m, Gravity = 9.81 m/s²:

• Step 1: \(\rho = 7850 \, \text{kg/m}^3\), \(g = 9.81 \, \text{m/s}^2\).
• Step 2: \(d = 0.05 \, \text{m}, A = \frac{\pi (0.05)^2}{4} \approx 0.0019635 \, \text{m}^2\).
• Step 3: \(L = 2 \, \text{m}\).
• Step 4: \(\gamma = \rho g = 77038.5 \, \text{N/m}^3\), \(W \approx 302.4 \, \text{N}, 30.83 \, \text{kg}, 67.96 \, \text{lb}\).

5. Frequently Asked Questions (FAQ)

Q: What is weight?
A: Weight is the force exerted by a material due to gravity, measured in N, kg, or lb.

Q: Why use multiple units?
A: The calculator provides results in N, kg, and lb for versatility across different standards.