WAVES AND ENERGY

Question 1

What is Energy?

Answer 1

The ability to do work or cause change; measured in joules (J).

Question 2

Forms of Energy

Answer 2

Kinetic, Potential, Thermal, Chemical, Electrical, Nuclear, Radiant, Mechanical.

Question 3

Kinetic Energy

Answer 3

Energy of motion; depends on mass and velocity (KE = 1/2 mv^2).

Question 4

Potential Energy

Answer 4

Stored energy due to position or state (e.g., gravitational, elastic, chemical).

Question 5

Thermal Energy

Answer 5

Energy related to heat and temperature; caused by particle movement.

Question 6

Chemical Energy

Answer 6

Stored in chemical bonds; released during chemical reactions (e.g., food, batteries).

Question 7

Electrical Energy

Answer 7

Energy from moving electrons (e.g., lightning, circuits).

Question 8

Nuclear Energy

Answer 8

Energy stored in atomic nuclei; released in fission and fusion.

Question 9

Radiant Energy

Answer 9

Energy carried by electromagnetic waves (e.g., light, X-rays, radio waves).

Question 10

Mechanical Energy

Answer 10

Sum of kinetic and potential energy in a system (e.g., a moving car).

Question 11

Law of Conservation of Energy

Answer 11

Energy cannot be created or destroyed, only transformed from one form to another.

Question 12

Examples of Energy Transformation

Answer 12

Chemical to mechanical (food to movement), electrical to thermal (heater), kinetic to potential (swinging pendulum).

Question 13

Renewable Energy Sources

Answer 13

Solar, wind, hydro, geothermal, biomass; naturally replenished.

Question 14

Non-Renewable Energy Sources

Answer 14

Fossil fuels (coal, oil, natural gas), nuclear; limited supply.

Question 15

Work and Energy Relationship

Answer 15

Work is done when energy is transferred to an object (Work = Force × Distance).

Question 16

Power

Answer 16

The rate of energy transfer; measured in watts (W).

Question 17

What is a Wave?

Answer 17

A disturbance that transfers energy through matter or space.

Question 18

Types of Waves

Answer 18

Mechanical Waves and Electromagnetic Waves.

Question 19

Mechanical Waves

Answer 19

Require a medium (solid, liquid, or gas) to travel through (e.g., sound, water waves).

Question 20

Electromagnetic Waves

Answer 20

Do not require a medium; can travel through space (e.g., light, X-rays, radio waves).

Question 21

Transverse Waves

Answer 21

Particles move perpendicular to wave direction (e.g., light, water waves).

Question 22

Longitudinal Waves

Answer 22

Particles move parallel to wave direction (e.g., sound waves).

Question 23

Parts of a Wave

Answer 23

Crest (highest point), Trough (lowest point), Wavelength (distance between two crests/troughs), Amplitude (height of wave).

Question 24

Wave Frequency

Answer 24

Number of wave cycles per second; measured in Hertz (Hz).

Question 25

Wave Speed Formula

Answer 25

Wave Speed = Frequency × Wavelength.

Question 26

Sound Waves

Answer 26

Mechanical longitudinal waves that travel through air, water, or solids.

Question 27

Light Waves

Answer 27

Electromagnetic transverse waves that do not need a medium to travel.

Question 28

Reflection

Answer 28

Bouncing back of a wave when it hits a surface (e.g., echo, mirror reflection).

Question 29

Refraction

Answer 29

Bending of a wave as it enters a new medium (e.g., pencil in water appears bent).

Question 30

Diffraction

Answer 30

Waves spreading out after passing through a gap or around obstacles.

Question 31

Interference

Answer 31

When two waves meet and combine (constructive or destructive).

Question 32

Doppler Effect

Answer 32

Change in frequency due to motion of the source or observer (e.g., ambulance siren changes pitch).

Question 33

Electromagnetic Spectrum

Answer 33

The range of all types of electromagnetic radiation, arranged by wavelength and frequency.

Question 34

Order of EM Spectrum (Lowest to Highest Frequency)

Answer 34

Radio Waves, Microwaves, Infrared, Visible Light, Ultraviolet, X-Rays, Gamma Rays.

Question 35

Visible Light Spectrum

Answer 35

The part of the EM spectrum that can be seen by the human eye.

Question 36

Colors of Visible Light (Lowest to Highest Frequency)

Answer 36

Red, Orange, Yellow, Green, Blue, Indigo, Violet (ROYGBIV).

Question 37

Red Light

Answer 37

Longest wavelength, lowest frequency, least energy.

Question 38

Violet Light

Answer 38

Shortest wavelength, highest frequency, most energy.

Question 39

Infrared Waves

Answer 39

Lower frequency than red light; used in heat sensors, night vision, and remote controls.

Question 40

Ultraviolet (UV) Waves

Answer 40

Higher frequency than violet light; can cause sunburn, used for sterilization.

Question 41

X-Rays

Answer 41

Even higher energy; used in medical imaging.

Question 42

Gamma Rays

Answer 42

Highest energy, shortest wavelength; used in cancer treatment and nuclear reactions.

Question 43

Radio Waves

Answer 43

Longest wavelength, lowest frequency; used in communication (radio, TV, cell phones).

Question 44

Microwaves

Answer 44

Shorter than radio waves; used in cooking, radar, and satellite communication.

Question 45

Infrared Waves

Answer 45

Used in remote controls, night vision, and detecting heat signatures.

Question 46

Visible Light

Answer 46

The only part of the EM spectrum visible to humans; colors range from red to violet.

Question 47

Ultraviolet (UV) Waves

Answer 47

Higher energy than visible light; used in sterilization and can cause sunburn.

Question 48

X-Rays

Answer 48

Used in medical imaging to see inside the human body.

Question 49

Gamma Rays

Answer 49

Highest energy, shortest wavelength; used in cancer treatment and emitted by nuclear reactions.