When a body is immersed partly or wholly in a liquid, there is an apparent loss in weight of the body which is equal to the weight of liquid displaced by the body.

Answer: Option C

Explanation:

Harry Brearley of England has invented Stainless Steel in 1913,

Electric iron has been invented by H.W. Seeley of USA in 1882,

Electromagent has been invented by W.Sturgeon of England in 1824,

Gramophone has been invented by T.A. Edison of USA in 1878.

Answer: Option D

Explanation:

Critical Velocity - The maximum velocity upto which fluid motion is streamline is called Critical Velocity.

Streamline Flow - If velocity of all fluid particles is same all the time then it can be said in streamline flow.

Terminal Velocity - When a body falls in viscous medium, its velocity first increases and finally becomes constant. The constant velocity is called terminal velocity.

Answer: Option B

Explanation:

coulomb is unit of Electric Charge,

watt per meter per degree celcius is unit of Thermal Conductivity,
joule per kilogram per Kelvin is unit of Specific Heat capacity.

Answer: Option B

Explanation:

Dyanamo - is used to convert mechanical energy into electrical energy,

Cyclotron - is a charged particle accelerator which can accelerate charged particles to high energies,

Electroscope - is used to detect the presence of an electric charge.

Answer: Option A