Fluid Mechanics — JEE physics STD 12 Science — Question

Assertion : Density is a derived physical quantity.
Reason : Density cannot be derived from the fundamental physical quantities.

Assertion : Tiny drops of liquid resist deforming forces better than bigger drops.
Reason : Excess pressure inside a drop is directly proportional to surface tension.

Assertion : If earth were a hollow sphere, gravitational field intensity at any point inside the earth would be zero.
Reason : Net force on a body inside the sphere is zero.

Assertion : Water at the foot of the water fall is always at different temperature from that at the top.
Reason : The potential energy of water at the top is converted into heat energy during falling.

Assertion : Gravitational potential of earth at every place on it is negative.
Reason : Every body on earth is bound by the attraction of earth.

Assertion : Although the surfaces of a goggle lens are curved, it does not have any power.
Reason : In case of goggles, both the curved surfaces have equal radii of curvature.

Assertion : Bulk modulus of elasticity (K) represents incompressibility of the material.
Reason : Bulk modulus of elasticity is proportional to change in pressure. Assertion : Strain is a unitless quantity. Reason : Strain is equivalent to force.

Assertion : Sterss is the internal force per unit area of a body.
Reason : Rubber is less elastic than steel.

Assertion : Short wave bands are used for transmission of radio waves to a large distance.
Reason : Short waves are reflected by ionosphere.