In engine has pistons in it that move back and forth inside a chamber. See fig below. Separating the piston from the valls of the chamber is a layer of oil that is $0\mathrm{.}004$ mm thick all around. The piston is a perfect cylinder that is $6\mathrm{.}7$ cm in liameter and $5$ cm long.

Based on the information provide below for the Kinematic viscosity and density of the oil, find the force required just to ivercome the friction between the cylinder and chamber walls in N at $25$ C when the piston is moving at $20\frac{m}{sec}?.$et's see if you can use the table to find enough info to lead you to the Dynamic viscosity.

'hen we'll see if y'all understand how shear stress leads you to a force.

'iston to wall clearance is $0\mathrm{.}004$ mm $.$