Dong nang bang 3 lan the nang thi $W_{d}=\frac{3}{4}W$ $<=>\frac{1}{2}m.v^2=\frac{3}{4}.\frac{1}{2}m.v^2_{max}$$<=>v=\pm \frac{\sqrt{3}}{2}v_{max}=\pm \frac{\sqrt{3}}{2}wA=\pm \frac{\sqrt{3}}{2}.A\sqrt{\frac{k}{m}}=\pm A\sqrt\frac{3k}{4m}$
Dong nang bang 3 lan the nang thi $W_{d}=\frac{3}{4}W$ $<=>\frac{1}{2}m.v^2=\frac{3}{4}.\frac{1}{2}m.v^2_{max}$$<=>v=\pm \frac{\sqrt{3}}{2}v_{max}=\pm \frac{\sqrt{3}}{2}\frac{kA}{m}$
Dong nang bang 3 lan the nang thi $W_{d}=\frac{3}{4}W$ $<=>\frac{1}{2}m.v^2=\frac{3}{4}.\frac{1}{2}m.v^2_{max}$$<=>v=\pm \frac{\sqrt{3}}{2}v_{max}=\pm \frac{\sqrt{3}}{2}
wA=\pm \frac{\sqrt{3}}{2}.A\sqrt{\frac{k
}{m}}=\pm A
\sqrt\frac{3k}{
4m}$