Guided Practice
Learn
In this guided practice lesson, you will apply your knowledge of wave properties and the electromagnetic spectrum to solve problems step by step. We will work through calculations and conceptual problems together.
Key Formulas Review
- Wave Speed: v = f × λ (velocity = frequency × wavelength)
- Period: T = 1/f (period is the inverse of frequency)
- Speed of Light: c = 3 × 10^8 m/s
- Energy and Frequency: Higher frequency = higher energy
Examples
Work through these examples to see the concepts in action.
Example 1: Calculating Wave Speed
A wave has a frequency of 500 Hz and a wavelength of 2 meters. What is its speed?
Solution: v = f × λ = 500 Hz × 2 m = 1000 m/s
Example 2: Finding Wavelength
A radio wave travels at 3 × 10^8 m/s with a frequency of 100 MHz. Find its wavelength.
Solution: λ = v/f = (3 × 10^8)/(100 × 10^6) = 3 meters
Example 3: Comparing EM Radiation
Which has more energy: red light or blue light?
Solution: Blue light has higher frequency, therefore higher energy.
✏️ Practice
Test your understanding with these practice questions.
Practice Questions
0/3 correctWhat is the scientific method's first step?
A hypothesis is:
Which is a property of matter?
Check Your Understanding
Test yourself with these 10 quiz questions.
Question 1: What is the relationship between frequency and wavelength?
Answer: Frequency and wavelength are inversely proportional. When frequency increases, wavelength decreases (if wave speed is constant).
Question 2: A wave has a period of 0.01 seconds. What is its frequency?
Answer: f = 1/T = 1/0.01 = 100 Hz
Question 3: What determines the speed of light in a vacuum?
Answer: The speed of light in a vacuum is a fundamental constant at approximately 3 × 10^8 m/s and is the same for all electromagnetic radiation.
Question 4: Calculate the wavelength of a wave traveling at 340 m/s with frequency 170 Hz.
Answer: λ = v/f = 340/170 = 2 meters
Question 5: Which type of wave can travel through a vacuum?
Answer: Electromagnetic waves can travel through a vacuum. Mechanical waves (like sound) require a medium.
Question 6: What happens to wave energy as frequency increases?
Answer: Wave energy increases as frequency increases. E = hf, where h is Planck's constant.
Question 7: A guitar string vibrates at 256 Hz. What is the period of vibration?
Answer: T = 1/f = 1/256 = 0.0039 seconds (approximately 3.9 milliseconds)
Question 8: Why do X-rays have more penetrating power than visible light?
Answer: X-rays have higher frequency and therefore more energy, allowing them to penetrate materials that visible light cannot.
Question 9: If you triple the frequency of a wave, what happens to its wavelength?
Answer: The wavelength becomes one-third of its original value (λ = v/f, so if f triples, λ decreases by factor of 3).
Question 10: What is the frequency of light with wavelength 600 nm (6 × 10^-7 m)?
Answer: f = c/λ = (3 × 10^8)/(6 × 10^-7) = 5 × 10^14 Hz
Next Steps
- Review any concepts that felt challenging
- Move on to the Lab Analysis lesson
- Return to practice problems periodically for review