An ideal fluid is a fluid that has zero viscosity. It results in a flow called as inviscid flow. In this flow re is no existence of shear force and viscosity vanishes.

With increase in temperature, coefficient of viscosity of fluid decreases. This happens due to weakening of bonds between molecules. Because of its dash pot coefficient, flow attains peak deformation.

Hydraulic radius is one of properties of a fluid flow in a channel. It controls water discharge. It also determines amount of work channel can do. (R_h=A/P). Thus, it is inversely proportional to loss of head due to friction.

Coefficient of static friction is defined as ratio of limiting frictional force to normal reaction force. Dividing dimensions of limiting frictional force and normal frictional force, units cancel out each or due to which it has no dimensions.

A crystalline substance does not undergo hydrogen bonding. A crystalline substance is a substance in which constituents are arranged in a highly ordered microscopic structure. It forms a crystal lattice in all directions.

A highly viscous oil will offer greater resistance due to which power loss is maximum. As we know, oil has a greater density than water. Thus, oil is more viscous than water and corresponds to a higher loss of power.

Shear modulus is also called as modulus of rigidity. It is defined as ratio of shear stress to shear strain. Since Young modulus is equal to stress by strain. The most suitable option is option c. (E= Young?s Modulus, v= poison?s ratio)

The dashpot timer is an automatic timer. It is used in several machines and has ?n? number of variations. It is used in many applications such as printing presses, generating motors and in many irrigation systems.

A flow through a circular pipe is said to be laminar when Reynolds number is below 2100. A more viscous fluid would have a higher velocity coefficient, thus reducing Reynolds number furr at same conditions. Hence, Reynolds number will be well below 2100. Flow will remain laminar.

Hooke?s law states that force is directly proportional to its extension. Hooke?s law is applicable within elastic limit, when body is deformed. Example: plucking strings of a guitar.