1.To answer the question “What is Damping?” Book Reference : Pages 45-46

What equipment do cars or bikes tend to have to iron out the bumps in the road? If the car suspension consisted only of springs, what would happen to the motion of the car for sometime after hitting a bump in the road? How would a pendulum continue to swing in an “ideal physics world” with no friction and a vacuum What do we observe in the “real-world”

Most vehicles use springs or similar to iron out the lumps and bumps With only springs the vehicle will continue to bounce (oscillate up and down) for some time after hitting the bump and the passengers would feel sea sick. Think SHM! Pendulum would keep going with full amplitude for ever Friction and air resistance reduce the amplitude until eventually the pendulum stops

Shock absorbers (dampers)

In the “real-world” a system in SHM such as a pendulum or a mass on a spring will eventually come to rest due to “losing energy”, actually doing work against friction and air resistance!

What will the ride in the car be like when 1.The damping is not strong enough 2.The damping is too strong 3.The damping is just right No bears, kitchen furniture, porridge or small girls with golden hair were harmed in the making of this lesson

1.Light damping (under damping) 2.Heavy damping (over damping) 3.Critical damping

1.Light damping (under damping) The oscillation slowly dies away (exponential decay). Oscillations slowly die away 2.Heavy damping (over damping) The damping is so strong that the displaced object takes a long time to return to the equilibrium position and does not oscillate 3.Critical damping : just enough to stop the oscillation as quickly as possible often about T/4 little or no overshoot

What caused this? How could it be avoided?

Caravan Stabiliser : Friction is introduced into the tow mechanism to damp both sideways and up and down motion

1)State is damping is light critical or heavy in these cases: A child on a swing, displaced and released Oil in a U shaped tube displaced from equilibrium and released 2)What would happen if the oil in a damper (shock absorber) was replaced with very viscous (thick) oil?