Scenario
Wrecking balls were common sights in the 1950s and 1960s and used to demolish large buildings. A wrecking ball is like a pendulum. The massive metal ball is same as a bob on a pendulum. It can be held in position by a chain directly above a structure and then released in free fall.Based on the evidence, write a scientific explanation to describe the energy changes that occur while the pendulum is in motion.
Claim
Evidence
Reasoning
Claim: The energy changes that occur while the wrecking ball pendulum is in motion involve the conversion of potential energy to kinetic energy and back to potential energy.
Evidence: When the wrecking ball pendulum is held in position above the structure, it has potential energy due to its position in the Earth's gravitational field. As the ball is released and swings towards the building, this potential energy is converted into kinetic energy as the ball gains speed and momentum. When the ball collides with the building, some of this kinetic energy is transferred to the structure, causing it to break apart. The rest of the kinetic energy is dissipated as sound and heat. As the wrecking ball swings back away from the building, this kinetic energy is converted back into potential energy as the ball rises higher above the ground.
Reasoning: The transformation of potential energy to kinetic energy and then back again is consistent with the law of conservation of energy, which states that energy cannot be created or destroyed, only transferred or transformed. In the case of the wrecking ball pendulum, potential energy is first converted to kinetic energy as the ball swings towards the building, then back to potential energy as the ball swings away. This energy transformation is what allows the wrecking ball to demolish the building efficiently.