All Exams Test series for 1 year @ ₹349 only
Question

For a symmetrical channel section with a moment of inertia I = 9.45 x $10^7$ $mm^4$ and an xx area A = 4500 $mm^2$, what is its radius of gyration $k_{xx}$ ? 

This question was previously asked in
RRB JE 2025 CBT 2 Mechanical and Allied Engg Question Paper English (2-Jul-2026) (Shift-1)
The correct answer is

144.92 mm

To find the radius of gyration k of the channel section, we can use the formula for the radius of gyration:

k = \sqrt{\frac{I}{A}}

Where:

  • I = Moment of inertia = 9.45 \times 10^7 \, \text{mm}^4
  • A = Area = 4500 \, \text{mm}^2

Substitute the values into the formula:

k = \sqrt{\frac{9.45 \times 10^7}{4500}}

Calculate the division inside the square root:

k = \sqrt{21000}

Now compute the square root:

k \approx 144.91 \, \text{mm}

Hence, the radius of gyration is approximately 144.92 mm.

This matches the correct answer, which confirms that the answer is 144.92 mm.

Was this answer helpful?

Important Questions from General Design Principles

  1. Pick up the correct statement from the following:

  2. The yield strength for a mild steel specimen was found to be 250 N/mm2. Taking a safety factor of 2, find out the working stress.

  3. As per IS 800:2007, the maximum effective slenderness ratio for a steel member always subjected to tension force is ______.

  4. Response reduction factor for ductile shear wall with special RC moment resisting frame as per IS 1893 (part 1):2002 is:

  5. As per IS: 800-2007, the area of splice plates shall exceed the area of the flange element spliced by at least

Need Expert Advice?
Test Series
RRB JE img
Railways
RRB JE (CBT 1 + CBT 2) 2026 Mock Test Series
1509 Tests 19 Tests Free
242 Attempts
4.3(107)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App