Pneumatic tool Pneumatic tool A pneumatic tool, air tool, air-powered tool or pneumatic-powered tool is a type of power tool, driven by compressed air, supplied by an air compressor. Pneumatic tools can also be driven by compressed carbon dioxide () stored in small cylinders allowing for portability. Most pneumatic tools convert the compressed air to work using a pneumatic motor. Compared to their electric power tool equivalents, they are safer to run and maintain, without risk of sparks, short-circuiting or electrocution, and have a higher power to weight ratio, allowing a smaller, lighter tool to accomplish the same task. Furthermore, they are
Electric potential energy time-invariant electric fields. The electric potential energy of a system of point charges is defined as the work required assembling this system of charges by bringing them close together, as in the system from an infinite distance. ^\mathbf{r} q\mathbf{E}(\mathbf{r'}) \cdot \mathrm{d} \mathbf{r'}</math>, The electrostatic potential energy can also be defined from the electric potential as follows: The SI unit of electric potential energy is the joule (named after the English physicist James Prescott Joule). In the CGS system the erg is the unit of energy, being equal to 10 J. Also electronvolts may be used, 1 eV = 1.602×10 J.