The plate, with side lengths (

L

) and mass

(m)

, is moving on an inclined plane only under its own weight at a constant speed

(U)

, with the shape of a square. There is oil between the plate and the inclined plane with thickness (h) and viscosity. , viscosity of the oil=0.026 Pa.s) (

L=100cm

, angle of inclination

=30

degrees,

h=0.8mm

) Assuming a linear velocity profile in the oil layer between the plate and the plane, derive and calculate the shear stresses at the plane

(y

)

=

(

0)

and on the plate

(y

)

=

(

h)

. Derive and calculate the expression for the mass of the block based on this velocity profile.\ Note: The translation assumes a technical context and may require further clarification based on the specific terminology used in the field.\