Physics Questions

Electric current produces a magnetic field. This magnetic field can be visualized as a pattern of circular field lines surrounding a wire.

A Mixture is a material made up of two or more different substances which are mixed.

Mixtures can be either homogeneous or heterogeneous.

* A homogeneous mixture is a type of mixture in which the composition is uniform and every part of the solution has the same properties.

* A heterogeneous mixture is a type of mixture in which the components can be seen, as there are two or more phases present.

Air is a homogeneous mixture of the gaseous substances nitrogen, oxygen, and smaller amounts of other substances.

This is a layer of atmosphere about 60 to 70 km above the earth and extends to about 400km. It contains ionised particles which can reflect radio waves making radio communication round the world possible.

Albedo refers to a material's ability to reflect sunlight. Since 30% of the sun's energy is reflected by the entire earth, the earth has an average albedo of 0.30.

Generally, dark surfaces have a low albedo and light surfaces have a high albedo.

$$\begin{gathered} 32oF \\ We know that \\ T(°F) = T(°C) × 1.8 + 32 \\ 32(°F) = 0(°C) \end{gathered}$$

Solar radiation instruments may be produced to measure different types of solar energy. When sunlight encounters the Earth's atmosphere, some of it is absorbed or scattered by water vapor, aerosols, clouds, and other air molecules. The radiation which penetrates to the Earth's surface is termed direct solar radiation.

A thermopile pyranometer is a type of actinometer used for measuring solar radiation on a planar surface and it is designed to measure the solar radiation flux density (W/m2) from the hemisphere above within a wavelength range 0.3 μm to 3 μm.