The radius of gyration of a body about an axis at a distance of 6 cm from its centre of mass is 10 cm. Then, its radius of gyration about a parallel axis through its centre of mass will be
A) 800cm
B) 8cm
C) 0.8cm
D) 80m
Correct Answer:
B
Solution :
\[\cos \phi =\frac{R}{\sqrt{{{R}^{2}}+{{\omega }^{2}}{{L}^{2}}}}\] \[\approx \frac{R}{\omega L}\] \[R<<\omega L\] Given, \[R<<\omega L\], Putting them, we get \[\cos \phi \]