A coiled Hookean spring is stretched 10 cm when a 1.5kg mass is hung from it. Suppose a 4 kg mass hangs from the spring and is set into vibration with an amplitude of 12 cm.

A. Find the force constant of the spring.
B. Find the Maximum restoring force acting on the vibrating body.
C. Find the period of vibration
D. Find maximum velocity and maximum acceleration of the vibrating object
E. Find the speed and acceleration when the displacement is 9cm

2 answers

500
a)kx^2=mg k=mg/x=1.5*9.8/0.1=147N/m
b)f=kx=147*.12=17.64N
c)T=2pi*sqrt(m/k)=2pi*sqrt(4/147)=1
d)Vmax=Aw w=sqrt(k/m)=6.1 Vmax=6.1*.12=.73m/s
amax=-Aw^2=-.12*6.1^2=-4.4m/s^2
e)V=L/t