A cylinder is fitted with a piston, beneath which is a spring, as in the drawing. The cylinder is open at the top. Friction is absent. The spring constant of the spring is 3900 N/m. The piston has a negligible mass and a radius of 0.020 m.

a) When air beneath the piston is completely pumped out, how much does the atmospheric pressure cause the spring to compress?
b) How much work does the atmospheric pressure do in compressing the spring?

Question

A cylinder is fitted with a piston, beneath which is a spring, as in the drawing. The cylinder is open at the top. Friction is absent. The spring constant of the spring is 3900 N/m. The piston has a negligible mass and a radius of 0.020 m.

a) When air beneath the piston is completely pumped out, how much does the atmospheric pressure cause the spring to compress? 
  b) How much work does the atmospheric pressure do in compressing the spring?

anonymous · Answer

the spring constant of the spring is 3900 n/m?..

anonymous · Answer

yes it is

anonymous · Answer

The force on the piston is atmospheric pressure (i don't know what value you use) times surface area of the piston.  F=-kx, where F is force -k is spring constant and x is distance the spring compresses, solve for x

anonymous · Answer

thanks ill try it out

anonymous · Answer

thanks i solved the first part, do you know which formula i should use for b)

anonymous · Answer

Work(w) is just Force(F) times Distance(x)

anonymous · Answer

w = fx, you know the force already and you just solved for x right? (the distance the spring compressed)

anonymous · Answer

gotcha, thanks so much

anonymous · Answer

np