Physics Quiz 2

The kilowatt-hour (kWh) is a unit of energy equal to one kilowatt of power sustained for one hour and is commonly used as a measure of electrical energy. One kilowatt-hour is equal to 3600 kilojoules.

When the pendulum is taken to the moon, the value of 'g' will decrease and hence time period will increase.

Heat transfer horizontally within the atmosphere is called advection. Advection is the transfer of heat or matter by the flow of a fluid, especially horizontally in the atmosphere or the sea. The horizontal movement of the air is comparatively more significant than the vertical movement.

When warm air (over the fire spot) rises, the air pressure at that place gets lowered. But around it, pressure is high so the air rushes from high-pressure zone to low-pressure zone giving an appearance of fanning the fire.

When a bar magnet is cut perpendicular to its length then the pole strength of each piece remains the same (but the magnetic moment is halved). If a magnet is cut parallel to its length then the pole strength of the pieces becomes half.

Sonar is a device that uses sound waves to detect and range objects on or under the surface of the water.

An anemometer is an instrument that measures wind speed and wind pressure. Anemometers are important tools for meteorologists, who study weather patterns.

The air layer between two shirts behaves like insulating media. Air in general is a good thermal insulator, but it can transmit heat through convection. However, if the air pockets inside the insulating material are separated from each other, heat flow from one air pocket to another cannot happen easily.

The Plimsoll line is a reference mark located on a ship's hull that indicates the maximum depth to which the vessel may be safely immersed when loaded with cargo.

The sky appears blue when the scattering of light takes place. As there is no atmosphere in space and hence light does not scatter into its constituent colours that is why the sky appears dark instead of blue to an astronaut in space.