Question

energy scenarios: text - read the text below to identify areas of potential energy, kinetic energy, and energy transformation

key: potential energy, kinetic energy, energy transformation

1. adapted from harry potter and the goblet of fire by j. k rowling

harry began to fly first this way then the other not near enough to make her breathe fire to stave him off, but still posing a sufficient threat to ensure she kept her eyes on him. her head swayed this way and that, watching him out of those vertical pupils, her fangs bared.

he flew higher. the horntail’s head rose with him, her neck stretched to its fullest extent, still swaying, like a snake before its charmer.

harry rose a few more feet and she let out a roar of frustration. he was like a fly to her, a fly she was longing to swat, her tail thrashed again, but he was too quick to now. she shot fire into the air, which he dodged. her jaws opened wide.

“come on,” harry hissed, swerving tantalizingly above her. “come on... come and get me... up you get now.”

and then she reared, spreading her great black leathery wings at last as wide as those of a small airplane - and harry dived. before the dragon knew what he had done, or where he had disappeared to, he was speeding toward the ground as fast as he could go, toward the eggs now unprotected by her clawed front legs. he had taken his hands off his firebolt, he had seized the golden egg

Explanation:

To identify areas of potential energy, kinetic energy, and energy transformation in the text, we analyze each part:

Potential Energy

• Dragon’s position (before action): When the dragon is “posing a threat” but not moving, it has potential energy (stored energy due to position/state, e.g., gravitational potential energy if elevated, or chemical potential energy for fire - breathing).
• Harry’s broom (before flying): If Harry’s broom is stationary (e.g., when he is preparing to fly), it has potential energy (gravitational, based on height).

Kinetic Energy

• Harry flying: When Harry “began to fly” and “flew higher,” his motion (and the broom’s) involves kinetic energy (\( KE=\frac{1}{2}mv^2 \), where \( m \) is mass, \( v \) is velocity).
• Dragon’s movements: The dragon “swaying,” “head rose with him,” “tail thrashed,” and “shot fire” involve motion, so these actions have kinetic energy (movement of the dragon’s body or fire - related motion).
• Harry diving: When Harry “dived” toward the ground, his downward motion involves kinetic energy.

Energy Transformation

• Dragon’s fire - breathing: Chemical potential energy (in the dragon’s body) transforms into thermal (heat) and kinetic energy (motion of fire) as it “shot fire into the air.”
• Harry’s flying/broom: Chemical potential energy (in Harry’s body or broom’s fuel, if applicable) transforms into kinetic energy (motion) and gravitational potential energy (if height changes). For example, when he flies higher, kinetic energy may convert to gravitational potential energy; when he dives, gravitational potential energy converts to kinetic energy.

Final Answer (Summary of Identified Areas)

• Potential Energy: Dragon at rest (posing threat), Harry’s broom at rest (before flight), elevated positions of dragon/Harry.
• Kinetic Energy: Harry flying/diving, dragon swaying/thrashing/fire - shooting.
• Energy Transformation: Dragon’s chemical energy → thermal/kinetic (fire); Harry’s/broom’s chemical energy → kinetic/gravitational potential (flight); gravitational potential → kinetic (diving).

Answer:

To identify areas of potential energy, kinetic energy, and energy transformation in the text, we analyze each part:

Potential Energy

• Dragon’s position (before action): When the dragon is “posing a threat” but not moving, it has potential energy (stored energy due to position/state, e.g., gravitational potential energy if elevated, or chemical potential energy for fire - breathing).
• Harry’s broom (before flying): If Harry’s broom is stationary (e.g., when he is preparing to fly), it has potential energy (gravitational, based on height).

Kinetic Energy

• Harry flying: When Harry “began to fly” and “flew higher,” his motion (and the broom’s) involves kinetic energy (\( KE=\frac{1}{2}mv^2 \), where \( m \) is mass, \( v \) is velocity).
• Dragon’s movements: The dragon “swaying,” “head rose with him,” “tail thrashed,” and “shot fire” involve motion, so these actions have kinetic energy (movement of the dragon’s body or fire - related motion).
• Harry diving: When Harry “dived” toward the ground, his downward motion involves kinetic energy.

Energy Transformation

• Dragon’s fire - breathing: Chemical potential energy (in the dragon’s body) transforms into thermal (heat) and kinetic energy (motion of fire) as it “shot fire into the air.”
• Harry’s flying/broom: Chemical potential energy (in Harry’s body or broom’s fuel, if applicable) transforms into kinetic energy (motion) and gravitational potential energy (if height changes). For example, when he flies higher, kinetic energy may convert to gravitational potential energy; when he dives, gravitational potential energy converts to kinetic energy.

Final Answer (Summary of Identified Areas)

• Potential Energy: Dragon at rest (posing threat), Harry’s broom at rest (before flight), elevated positions of dragon/Harry.
• Kinetic Energy: Harry flying/diving, dragon swaying/thrashing/fire - shooting.
• Energy Transformation: Dragon’s chemical energy → thermal/kinetic (fire); Harry’s/broom’s chemical energy → kinetic/gravitational potential (flight); gravitational potential → kinetic (diving).