A single degree of freedom system having mass 1 kg and stiffness 10kN/...
Milliseconds. Find the displacement and velocity of the system after the impulse.
We can use the impulse-momentum equation to solve this problem:
impulse = change in momentum
The impulse is given by the magnitude of the force multiplied by the duration of the force:
impulse = 5 kN * 10 ms = 50 Ns
The initial momentum of the system is zero, since it is initially at rest. Therefore, the change in momentum is equal to the final momentum:
change in momentum = final momentum
The final momentum can be expressed in terms of the displacement and velocity of the system:
final momentum = m * v = 1 kg * v
where v is the velocity of the system after the impulse.
The displacement can be found using the equation of motion for a single degree of freedom system:
m * x'' + k * x = f(t)
where x'' is the second derivative of displacement with respect to time, k is the stiffness, and f(t) is the applied force. Since the system is initially at rest, we can assume that the displacement at t=0 is zero. The impulse force can be modeled as a delta function, so f(t) = 5 kN * delta(t-10 ms).
Using Laplace transforms, we can solve for the displacement:
s^2 * X(s) + 10^4 * X(s) = 5 * 10^3 * e^(-10s)
X(s) = 5 * 10^3 / (s^2 + 10^4) * e^(-10s)
Taking the inverse Laplace transform, we get:
x(t) = 5 * 10^3 / 10^4 * (1 - e^(-10t) * cos(10^4 t))
At t=10 ms, the displacement is:
x(10 ms) = 5 * 10^3 / 10^4 * (1 - e^(-1) * cos(100)) ≈ 0.305 mm
To find the velocity, we can take the derivative of the displacement:
v(t) = dx/dt = 5 * 10^3 / 10^4 * (10e^(-10t) * sin(10^4 t) - e^(-10t) * 10^4 * cos(10^4 t))
At t=10 ms, the velocity is:
v(10 ms) = 5 * 10^3 / 10^4 * (10e^(-1) * sin(100) - e^(-1) * 10^4 * cos(100)) ≈ -4.269 m/s
Therefore, the displacement is approximately 0.305 mm and the velocity is approximately -4.269 m/s after the impulse.
A single degree of freedom system having mass 1 kg and stiffness 10kN/...
Wn=√10000/1
=100rad/sec
initial velocity is 0
F*t=m(Vo-Vi)
(5*10^3*10^-4)=1(Vo-0)
0.5=1(Vo)
Vo=0.5m/s
X=Vo/Wn
=0.5/100
=0.005 m OR
=5 mm
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