A blacksmith strikes a piece of metal with a hammer repeatedly. The nettle slowly begins to glow as the temperature increases, and the metal becomes more malleable which changes on a microscopic level lead to the visible changes in the properties of the metal was it the average speed of the particles increased, or is it the potential energy of the particles decreased or is it the kinetic energy of the particles decreased or is it the individual temperature of the particles increased?

As the blacksmith strikes the metal with a hammer, the average speed of the particles increases. This is because the impact transfers energy to the metal, causing the particles to vibrate and move faster. The increase in average speed of the particles leads to an increase in temperature, making the metal glow. Additionally, the kinetic energy of the particles increases due to their faster movement. The potential energy of the particles, however, does not decrease significantly in this scenario. Therefore, the correct answer is that the average speed of the particles increases and the kinetic energy of the particles increases as well.