Question
do not copy and paste answer from another question. I won't rate it.
Shown in the figure is an ideal spring hanging from a ceiling. When a mass 7.15 kg is attached to the spring (as shown in the middle system), the spring stretches by 0.0205 m. The mass is then pushed up from its equilibrium position 0.0410 m and released, as shown on the far right. Calculate the kinetic energy the mass possesses when passing through the equilibrium position. On the right is a plot of the displacement of the mass with time, with t = 0 (far left portion of the graph) corresponding to the moment the mass was released. Which of the following most closely approximates the velocity of the mass at the point located in the figure? (Consider "up" the positive direction.) -A omega sin(14pi/8) Acos(14pi/8) A omega sin(7/8) A omega sin(14pi/8) -A omega cos(7/8)
Explanation / Answer
angular frequency=W=(k/m)^1/2=(g/x)^1/2=(9.81/0.0205)^1/2=21.875 rad/s
K.E=1/2M*A^2*W^2=1/2*7.15*0.0410^2*21.875^2=2.875 J
a)V=-AWsin(14pi/8)
