The light from the sun heats a metal surface. this is an example of what?
a; radiation
b; conduction
c; convection
d; reflection

The correct answer is radiation.

Explanation:

There are three method of transfer of energy: conduction, convection and radiation.

In conduction, there is no actual movement of the particle. There is conduction in the solid. Heat is transferred from hotter end of an object to cold end of the particle.

In convection, there is actual movement of the particle. Both liquid and gases can transfer heat energy by convection.

In radiation, it does not require particles in its transfer of energy. In the given problem, the light from the Sun heats a metal surface. This is an example of radiation.

Therefore, the option is A.

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .

d) physical means can be used to separate the components of air.