Which of the following formulae is/are used to find the buckling load in columns?
1. Euler's formula
2. Rankine Gordon formula
3. Johnson's parabolic formula
4. IS formula
1
Only 1, 2 and 4
2
Only 1
3
All 1, 2, 3 and 4
4
Only 1 and 2
Which of the following formulae is/are used to find the buckling load in columns?
1. Euler's formula
2. Rankine Gordon formula
3. Johnson's parabolic formula
4. IS formula