For a cantilever of effective depth of 0.5 m, the maximum span to satisfy vertical deflection limit is A. 3.5 m B. 4 m C. 4.5 m D. 5 m

The correct answer is B. 4 m.

The maximum span to satisfy vertical deflection limit is calculated using the following formula:

$L_m = \frac{5}{3} \cdot \frac{d^2}{f_c} \cdot \frac{1}{1 + \frac{h}{L}}$

where:

• $L_m$ is the maximum span (m)
• $d$ is the effective depth (m)
• $f_c$ is the compressive strength of concrete (MPa)
• $h$ is the height of the beam (m)
• $L$ is the span (m)

For a cantilever of effective depth of 0.5 m and compressive strength of concrete of 25 MPa, the maximum span to satisfy vertical deflection limit is:

$L_m = \frac{5}{3} \cdot \frac{0.5^2}{25} \cdot \frac{1}{1 + \frac{0.5}{4}} = 4 \text{ m}$

Option A is incorrect because it is less than the calculated value. Option C is incorrect because it is greater than the calculated value. Option D is incorrect because it is not a valid option.