In the second Iron Man movie, Iron Man effortlessly pushes a Rolls Royce with his foot about 10 meters to get his friends out of danger. I thought to myself that Iron Man must weigh a lot for him to push the car like that without moving.
Using kinematics and Newton's second law, I figured out how much Iron Man's suit weighs. Using the internet, I found that:
Car's friction coefficient (u1) = 0.7
Mass of car = 2630.84 kg
Iron Man's friction coefficient (estimated based on iron's friction coefficient with other materials) (u2) = 0.2
Estimated distance of initial acceleration (the push) = 0.5 m
Using the force of friction, I found out the top speed after the push. From there I was able to find the acceleration of the push.
Ffr = u1FN = u1mg = 0.7*2630.84*9.8 = 18047.56 N
Ffr = ma --> a = 6.86 m/s^2
vf^2 = vi^2 + 2ax --> 0 = vi^2 + 2(-6.86)(10) --> vi = 11.71 m/s
vf^2 = vi^2 + 2ax --> 11.71^2 = 0^2 + 2a(0.5) --> a = 137.12 m/s^2
With the acceleration of the push, I was able to find the mass of Iron Man.
Fp = ma = 360740.78N
Ffr = u2FN = u2mg = Fp --> 360740.78 = 0.2*9.8*m --> m = 184051.42 kg
Iron Man is very heavy. However, magically, his suit can pack up into a briefcase, which his girlfriend can carry around with her.