Water near the bed of a deep river is quiet while that near the surface flows. Give reasons.

The stone of a hand flour grinder is provided with a handle near its rim. Give reason.

When the rivers and lakes start freezing, the weather becomes warm. Give reason.

We spread the clothes while drying. Give reason.

The velocity of water in river is 180 km h^(-1) near the surface .If the river is 5 m deep,then the shearing stress between the surface layer and the bottom layer is ( coefficient of viscosity of water eta =10^(-3) Pa s)

Assertion: The surface charge densities of two spherical conductors of different radii are equal. Then the electric field intensities near their surface are also equal. Reason: Surface charge density is equal to charge per unit area.

A frog lives in water or near water because

A frog lives in water or near water because

Asseration: A metal piece and a non-metal (stone) piece are dropped from the same height near earth's surface. Both will reach the earth's surface simultaneousely. Reason: There is no effect of earth's magnetic field on freely falling body.

The temperature of water at the surface of a deep lake is 2^@C . The temperature expected at the bottom is

Drops of water are seen on the outer surface of a vessel containing chilled water. Give reason.