While these fluids have pouring/spraying properties they can semi solidify if a force is applied to them
The other way round. When a force (spraying) is applied the fluid reduces its viscosity because of sheer stresses. When the force is removed viscosity increases. Thats why you have to hit the tomato sauce bottle to get the stuff out, the act of hitting reduces the sheer stresses thus lowering the viscosity - the fluid is said to have thixotropic properties.