Physics Questions

To produce controlled energy i.e energy at a controlled or steady rate, the number of fissions per second must be controlled and maintained at that rate. Excess neutrons should be absorbed by control roads like cadmium.

During convection, cool and dense air falls through the warmer and less dense air. The warm air having less mass is being displaced by the cooler which is much heavy. Convection always involves the air rising through the atmosphere.

Gear Lapping is an operation after heat treatment. Gear lapping is the process of imparting a very fine finish and high degree of accuracy to gear teeth, by using a lapping tool and applying a fine-grained abrasive between a work material and a closely fitting surface, called a lapping plate.

Parabola, because when the coin is dropped at a particular point, it has the same velocity as the running train. So by Newton's first law, it continues its motion horizontally with that velocity. But then, it is also pulled down by earth's gravity continuously. In this situation its horizontal motion gives way to the parabolic motion until it reaches the ground.

Cohesion refers to attraction between molecules of the same kind while adhesion refers to attraction between different kinds of molecules

Light year is the unit of to express astronomical distances, that light can travel in one year. Light moves at a velocity of about 300,000 kilometers (km) each second. So in one year, it can travel about 10 trillion km. More precisely, one light-year is equal to 9,500,000,000,000 kilometers.

Approximately, 1 light year = 10^16 mts.

As it is said that density of gold is greater than that of density of silver, so silver occupies a greater volume than gold. So it has more upthrust from the water, although they both show the same weight under water, there is more silver present. Hence silver piece will weigh more.