Answer:
50 N/mm²
Step-by-step explanation:
To determine the maximum normal stress in the bar ABCD, you need to find the maximum force experienced by the bar and then use the formula for normal stress, which is:
[tex][ \sigma = \frac{F}{A} ][/tex]
where:
[tex](\sigma) is the normal stress,(F) is the force applied,(A) is the cross-sectional area.[/tex]
From the information provided:
[tex]Cross-sectional area, (A = 600 \text{ mm}^2).Forces acting on different sections of the bar are 25 kN, 20 kN, and 30 kN.[/tex]
First, we need to convert the forces to Newtons (1 kN = 1000 N):
• 25 kN = 25,000 N
• 20 kN = 20,000 N
• 30 kN = 30,000 N
Next, we identify the maximum force, which is 30,000 N.
Finally, we calculate the maximum normal stress:
[tex][ \sigma_{\text{max}} = \frac{F_{\text{max}}}{A} = \frac{30,000 \text{ N}}{600 \text{ mm}^2} = 50 \text{ N/mm}^2 ][/tex]
Therefore, the maximum normal stress in the bar is 50 N/mm².