Physics Questions

Materials that usually allow electricity to pass through them are called Good conductors of electricity.

Conductors conduct electrical current very easily because of their free electrons.

Examples are :: Aluminium, Gold, Copper, Silver

Materials that do not allow or oppose electrical current & make poor conductors are called Insulators.

Examples are :: Glass, Plastic, Wood, Air,...

Glass is made from heating of sand. To melt sand to make glass, the temperature needed is above 1800 deg celcius.

Infrared radiation, what we experience as heat when we hold our hand near a warm object, is somewhat longer wavelengths than visible light. Visible light is simply electromagnetic radiation in a range of wavelengths that our eyes are sensitive to. Visible wavelengths range from 0.0007 milimeters for red light, through orange, yellow, green, and blue, to 0.0004 milimeters for violet light. Ultraviolet is shorter wavelengths than violet.

Longer the wavelength,lower the energy

Electric power is the rate per unit time, at which electrical energy is transferred by an electric circuit. The power of electricity is measured in watts and kilo watts.

1 Watt is the unit of electrical power equal to one ampere under the pressure of one volt.

Energy can be either potential or kinetic. The energy associated with motion is called Kinetic energy and similarly, the energy associated with position is called Potential energy.