I would like to have some help figuring out how many people that is needed in order to lift a car (and how you would calculate it). Here is an example of the problem:
Mass: 500 kg
Length of the bottom of the car: 2,5 m
Width of the bottom of the car: 1 m
Height of the car: 1,5 m
Let's assume the car is shaped as a regular box. Let's assume that the mass is distributed evenly throughout the box.
All the people to lift are placed around the car with equal distance between each other (if you drew a polygon connecting everyone, all the sides of the polygon would have the same length).
Everyone is holding underneath the bottom of the car. Let's assume they all lift vertically.
Everyone lifting is able to lift the same amount of weight in a "dead-lift" (like when the bodybuilders lift a heavy ball, where they use their thigh-muscles to lift the weight). They can all lift 80 kg from ground level to 1 m above ground level this way.
Let's assume that the tires are pumped so hard, that they only touch the ground with 1 cm^2 of tire each. We can forget about the spring effect in the tyres.
No tools can be used.
How many people will it take to lift the car 0,2 m off the ground?
If I have forgotten to supply some information, please let me know, and I will.
Thanks a lot for the help.