# Mechanical Engineering - Strength of Materials - Discussion

Discussion Forum : Strength of Materials - Section 5 (Q.No. 1)
1.
The maximum shear stress in a thin cylindrical shell subjected to internal pressure p is
pd/t
pd/2t
pd/4t
pd/8t
Explanation:
No answer description is available. Let's discuss.
Discussion:
30 comments Page 1 of 3.

Surya said:   7 months ago
Yes, sir, the answer is C.

We should consider hoop and radial stress for calculation.

Sachin Tatrari said:   4 years ago
I think C is the correct one, when not mentioned properly, we take absolute shear stress and absolute shear stress will be the maximum of all three shear stresses which we will get after subtracting hoop stress(pd/2t), longitudinal stress(pd/4t) and the radial stress (ZERO in this case) with each other one by one and then dividing it by 2. Here we are getting maximum absolute shear stress when we will subtract hoop stress with radial stress and then divide it by 2 i.e. (pd/2t - 0)/2 = pd/4t. So option C is correct.
(5)

Jay Thapar said:   4 years ago
I agree, D is the correct answer.

Abhishek said:   4 years ago
(1)

Subrato said:   4 years ago
Maximum shear stress in the plane is pd/8t but here it is not mentioned that it is in the plane. There are two shear stresses one is in the plane and the other is out of the plane. So the maximum shear stress is pd/4t that is out of plane stress. That's why the correct answer is pd/4t that is option C.
(1)

Tarik said:   4 years ago
As In-plane shear is not mentioned Answer should be C.

Pankaj Kumar Das said:   4 years ago
For Max Shear Stress- [C]. pd/4t and For Max IN PLANE shear stress it is [D]. pd/8t.
(1)

Manish said:   4 years ago
Max shear stress = 1/2 (max. Principal-min. Principal stress).

Now max. Principal stress = hoops (pd/2t).

Also, min principal stress= radial (-P= approx 0 as compared to other stresses, so it is taken as 0).

So now, solve for this and we get : max shear stress as = pd/4t which is also known as absolute maximum shear stress.

And pd/8t is max. Wall shear stress.
(2)

Mayur Desai said:   5 years ago
Maximum shear stress = 1/2(max. Principal stress- Min. Principal stress).
So, the right answer is D.

Rakesh said:   5 years ago
Option C is correct a/c max shear stress theory.
(1)