Find the elastic deformation energy of a steel rod whose one end is fixed and the other is twisted through an angle φ=6.0∘\varphi=6.0^{\circ}φ=6.0∘. The length of the rod is equal to l=1.0 m,l=1.0 \mathrm{~m},l=1.0 m, and the radius to rrr =10 mm=10 \mathrm{~mm}=10 mm