Physical properties of materials

A sudden fall in barometer reading indicates that the weather will be :

Consider the figure of a fountain with four holes, given below: Which one of the holes in the fountain will throw the water farthest?

A liquid is flowing in a streamlined manner through a cylindrical pipe. Along with a section containing the axis of the pipe, the flow profile will be:

With the rise of temperature, the viscosity of liquid:

The highest viscosity among the following is of:

Which one of the following is most viscous?

Assertion (A): With the increase of temperature, the viscosity of glycerin increases. Reason (R): Rise of temperature increases kinetic energy of molecules. Code: (a) Both (A) and (R) are true, and (R) is the correct explanation of (A). (b) Both (A) and (R) are true, but (R) is not the correct explanation of (A). (c) (A) is true, but (R) is false. (d) (A) is false, but (R) is true.

The surface of a lake is frozen in severe winter, but the water at its bottom is still liquid. Why? Following are some options: (a) Ice is a bad conductor of heat (b) Since the surface of the lake is at the same temperature as the air, no heat is lost (c) The density of water is maximum at 4°C (d) None of the above

In cold weather, aquatic animals survive even when water at the top layer of the lake freezes into ice because—

Fish can survive in a frozen lake because—