This is undercarriage from an American DC3 used in the Berlin airlift. Notice that the pole attached to the wheel is designed to go up into the grey tube above it. There will be suspension and shock absorbers. I'm not sure how the suspension is done in this case, but perusal of the Internet suggests that some modern aircraft use an airbag that compresses as the force of landing pushes the wheel up. This is like bending your knees when you jump down. It increases the time to stop which reduces the rate of change of momentum, thus decreasing the force of impact. Unless you include shock absorbers, it is likely that the suspension will spring backwards and forwards making the aeroplane wobble up and down. On a car, a shock absorber is a metal plate that gets dragged slowly through a viscous liquid. There are a lot of assumptions here. I didn't realise how little I knew about the specifics of aeroplane landing gear. The Physics is correct, though.
