A blacksmith strikes a piece of metal with a hammer repeatedly. The metal slowly begins to glow as the temperature increases, and the metal becomes more malleable. Which changes on a microscopic level led to the visible changes in the properties of metal?
1. The average speed of the particles increased
2. The kinetic energy of the particles decreased
3. The potential energy of the particles decreased
4. The individual temperature of the particles increased
1. The average speed of the particles increased
3. The potential energy of the particles decreased
4. The individual temperature of the particles increased
The correct answers are 1 and 4.
1. The average speed of the particles increased: When the blacksmith strikes the metal with a hammer, the kinetic energy is transferred to the particles of the metal. This increases the average speed of the particles. As they gain more kinetic energy, they move faster, causing the metal to heat up.
4. The individual temperature of the particles increased: As the average speed of the particles increases, their individual temperature also increases. Temperature is a measure of the average kinetic energy of the particles. The increased kinetic energy of the particles leads to an increase in their temperature, resulting in the visible changes, such as glowing and increased malleability, in the metal.
The correct answer is 1. The average speed of the particles increased.
When a blacksmith strikes a piece of metal with a hammer, the repeated impacts transfer kinetic energy to the metal. This increase in kinetic energy causes the particles in the metal to vibrate more vigorously and move with greater speed on a microscopic level. As they move faster, the particles collide with each other more frequently and with greater force. This increased collision and molecular motion result in the conversion of kinetic energy to thermal energy.
The transfer of kinetic energy to the particles causes an increase in their temperature. As the temperature rises, the metal begins to glow and becomes more malleable. This is because the increased kinetic energy allows the particles to overcome intermolecular forces more easily, making it easier to change the shape and structure of the metal.
Option 2, the kinetic energy of the particles decreasing, is incorrect. The kinetic energy of the particles actually increases as a result of the repeated hammer strikes.
Option 3, the potential energy of the particles decreasing, is also incorrect. The potential energy of the particles primarily depends on their position and the intermolecular forces between them.
Option 4, the individual temperature of the particles increasing, is indirectly true. The increase in temperature is a result of the increased kinetic energy, rather than the cause of the visible changes in the properties of the metal.