A viscous liquid is sheared between two parallel disks. The upper disk rotates and the lower one is fixed. The velocity field between the plates is given by

An ideal otto cycle has a compression ratio of 10.5, takes in air at 90 kpa and 40°c, and is repeated 2500 times per minute. using constant specific heats at room temperature, determine the thermal efficiency of this cycle and the rate of heat input if the cycle is to produce 90 kw of power.