Question

一质点沿着x轴作简谐振动,震动函数为x=0.05cos(2πt+1/3π),从t=0起到质点位置在x

x=-2.5cm处，且向x轴正方向运动的最短时间

Answer 1

x=0.05cos(2πt+1/3π)是x=0.05cos(2πt+π/3) m 吧？
-0.025=0.05cos(2πt+π/3),，则 cos(2πt+π/3)=-0.5 .，则2πt+π/3=2π/3 ,解得 t=1/6 (s)

Answer 2

x=0.05cos(2πt+1/3π)是x=0.05cos(2πt+π/3) m 吧？
-0.025=0.05cos(2πt+π/3),，则 cos(2πt+π/3)=-0.5 .，则2πt+π/3=2π/3 ,解得 t=1/6 (s) 。