All flashcards
Flashcard 1: Which energy form describes the energy of a moving object?
Answer: Kinetic energy. Energy possessed by any object in motion.
Flashcard 2: Identify the most common unwanted output in real devices that reduces efficiency.
Answer: Thermal energy (waste heat). Friction and resistance create unwanted heat.
Flashcard 3: Which energy conversion happens in a battery-powered toy car when it moves?
Answer: Chemical energy to mechanical energy. Battery chemicals power the motor to spin wheels.
Flashcard 4: What is thermal energy?
Answer: Heat energy from particle motion. Faster particles mean more heat.
Flashcard 5: Which energy conversion happens in a solar calculator?
Answer: Light energy to electrical energy. Solar panels convert sunlight to electricity.
Flashcard 6: What is electrical energy?
Answer: Energy from moving electric charges. Electrons flow through wires and circuits.
Flashcard 7: Which component in a simple circuit provides the energy source?
Answer: Battery (cell). Stores chemical energy for the circuit.
Flashcard 8: Which component converts electrical energy to light in a simple circuit?
Answer: Light bulb (lamp). Filament glows when electricity flows through.
Flashcard 9: What is mechanical energy?
Answer: Energy of motion or position of objects. Includes both kinetic and potential energy.
Flashcard 10: Which energy conversion happens in a toaster?
Answer: Electrical energy to thermal energy. Electric current heats metal coils.
Flashcard 11: What is a fair test when comparing two energy-conversion device designs?
Answer: Change one variable and keep others the same. Controls variables for accurate comparison.
Flashcard 12: Which energy conversion happens in a speaker when it plays music?
Answer: Electrical energy to sound energy. Electric signals vibrate the speaker cone.
Flashcard 13: Which energy conversion happens in a flashlight?
Answer: Chemical energy to light energy. Battery chemicals power the bulb to glow.
Flashcard 14: What is sound energy?
Answer: Energy carried by vibrations in matter. Waves travel through air, water, or solids.
Flashcard 15: What is light (radiant) energy?
Answer: Energy carried by light waves. Electromagnetic waves we can see.
Flashcard 16: Which term means energy is not destroyed, only changed in form?
Answer: Law of Conservation of Energy. Energy cannot be created or destroyed.
Flashcard 17: What is the output energy of a device?
Answer: The energy the device produces or delivers. Output is the final form after conversion.
Flashcard 18: What is the input energy of a device?
Answer: The energy that enters the device. Input is the starting form before conversion.
Flashcard 19: Which energy form is produced by vibrations that you can hear?
Answer: Sound energy. Energy carried by vibrating air molecules.
Flashcard 20: What is the energy conversion when a hand-crank generator lights an LED?
Answer: Mechanical energy to electrical energy to light energy. Hand motion generates electricity that powers LED.
Flashcard 21: What is the energy conversion in a wind turbine connected to a generator?
Answer: Kinetic energy of wind to electrical energy. Moving air spins turbine blades to generate power.
Flashcard 22: Find the correct energy conversion for a battery-powered buzzer: chemical → → sound.
Answer: Electrical energy. Battery's chemical energy becomes electricity first.
Flashcard 23: Which component is the best choice to convert light into electricity in a model device?
Answer: Solar cell (solar panel). Photovoltaic cells generate electricity from sunlight.
Flashcard 24: Which statement best describes the law of conservation of energy?
Answer: Energy is not created or destroyed; it only changes form. Fundamental principle that energy is conserved.
Flashcard 25: Identify the main input energy for a device that uses a solar panel to run a motor.
Answer: Light energy. Solar panels capture sunlight as primary energy source.
Flashcard 26: Identify the main output energy when a motor spins a fan blade to move air.
Answer: Mechanical (motion) energy. Fan blades create air movement as kinetic energy.
Flashcard 27: What is the energy conversion in a simple electric fan?
Answer: Electrical energy to mechanical (motion) energy. Electric current creates magnetic field that spins motor.
Flashcard 28: What is the energy conversion when a rubber band car moves forward?
Answer: Elastic potential energy to kinetic (motion) energy. Stored energy in stretched band releases as motion.
Flashcard 29: What is the energy conversion when a battery makes a small motor spin?
Answer: Chemical energy to electrical energy to mechanical energy. Battery powers motor through electrical current.
Flashcard 30: Which energy form is stored in a stretched spring or rubber band?
Answer: Elastic potential energy. Energy stored when material is stretched or compressed.