Calculate the energy of 1kg of concrete from 20⁰c to 30⁰c

9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.

Explanation:

In this exercise we need to determined the sensible heat store in a kilogram of concrete due to a change in temperature. Sensible heat (), measured in kilojoules, is defined by the following expression:

(1)

Where:

- Mass, measured in kilograms.

- Average specific heat of concrete, measured in kilojoules per kilogram-degree Celsius.

, - Initial and final temperatures of concrete, measured in degrees Celsius.

If we know that , , and , then the energy store in a kilogram of concrete is:

9 kilojoules of energy are stored in a kilogram of concrete due to sensible heat.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia