Define section modulus and neutral axis.

Define section modulus and neutral axis.
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1 Answer

Answer :

Section Modulus: It is the ratio of M. I. of the section about the neutral axis and the distance of the most extreme fiber from the neutral axis.

Neutral Axis: It is the axis shown in cross-section where bending stress is zero called as neutral axis.

OR

The intersection of the neutral layer with any normal cross section of a beam is called as neutral axis.
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The depth of neutral axis for a balanced section is --------- the depth of critical neutral axis [ A ] equal [ B ] always greater than [ C ] always less than [ D ] may be sometimes greater than

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A beam of T-section is subjected to a shear force of F. The maximum shear force will occur at the a. top of the section b. bottom of the section c. neutral axis of the section d. junction of web and flange

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Last Answer : a. 2.66 (S/bh)

What is the shear stress acting along the neutral axis of triangular beam section, with base 60 mm and height 150 mm, when shear force of 30 kN acts? a. 15.36 N/mm2 b. 10.6 N/mm2 c. 8.88 N/mm2 d. Insufficient data

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The ratio of the section modulus of a square section of side B and that of a circular section of diameter D, is (A) 2 /15 (B) 3 /16 (C) 3 /8 (D) /16

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A standard steel tape of length 30 m and cross-section 15 × 1.0 mm was standardised at 25°C and at 30 kg pull. While measuring a base line at the same temperature, the pull applied was 40 kg. If the modulus of elasticity of steel tape is 2.2 × 106 kg/cm2 , the correction to be applied is (A) - 0.000909 m (B) + 0.0909 m (C) 0.000909 m (D) None of these

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Last Answer : (A) - 0.000909 m

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Pick up the correct assumption of the theory of simple bending (A) The value of the Young's modulus is the same in tension as well as in compression (B) Transverse section of a beam remains plane before and after bending (C) The material of the beam is homogeneous and isotropic (D) All the above

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is the pre-stressed force applied to the tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The maximum stress in the beam, subjected to a maximum bending moment , is (A) f = (P/A) + (Z/M) (B) f = (A/P) + (M/Z) (C) f = (P/A) + (M/Z) (D) f = (P/A) + (M/6Z)

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Last Answer : Answer: Option C