Question

The stress in section AB is ______ Mpa. A) 22.5 B) 26.3 C) 28.8 D) 31.8 E) 44.2 F) 56.6 4. The stress in section BC is ______ Mpa.
A) 22.5

B) 26.3

C) 28.8

D) 31.8

E) 44.2

F) 56.6 5.


While under the load, the strain in section AB is ______x 10 -6 mm/mm.


A) 455

B) 808

C) 64,320

D) 125,300

E) 450,000

F) 722,300


6. While under the load, the strain in section BC is ______x 10 -6 mm/mm.


A) 455

B) 808

C) 64,320

D) 125,300

E) 45,000

F) 722,300


7. The total elongation of the bar while under the applied load is _____ mm.

A) 0.110

B) 0.322

C) 0.596

D) 12.5

E) 17.7

F) 18.3


8. Upon removal of the load, the permanent deformation of the bar is ______ mm.

A) 0.110

B) 0.322

C) 0.596

D) 12.5

E) 17.7

F) 18.3

Answer 1

Answer:

The stress in section AB is 31.8 Mpa

The stress in section BC is 56.6 Mpa

Explanation:

P.S - The exact question is -

As given,

$P_{A}$ = 10 KN , $P_{B}$ = 10 KN

d = 20 m for AB

d = 15 m for BC

Area of AB = $\frac{\pi }{4} (d)^{2} = \frac{\pi }{4} (20)^{2} = \frac{\pi }{4} (400) = 100\pi$

Now,

Stress in AB = $\frac{P_{A} }{Area} = \frac{10 KN}{100\pi } = \frac{10. 1000}{100\pi } = \frac{100}{\pi }$ = 31.8 Mpa

Now,

Area in BC = = $\frac{\pi }{4} (d)^{2} = \frac{\pi }{4} (15)^{2} = \frac{\pi }{4} (225) = 56.25\pi$

Now,

Stress in BC = $\frac{P_{B} }{Area} = \frac{10 KN}{56.25\pi } = \frac{10. 1000}{56.25\pi } = \frac{178.4}{\pi }$ = 56.6 Mpa