<< Chapter < Page Chapter >> Page >
Destructive interference
Destructive interference is when two pulses meet, resulting in a smaller pulse.
Superposition of two pulses. The left-hand series of images demonstrates destructive interference, since the pulses cancel each other. The right-hand series of images demonstrate a partial cancelation of two pulses, as their amplitudes are not the same in magnitude.

The two pulses shown below approach each other at 1 m · s - 1 . Draw what the waveform would look like after 1 s , 2 s and 5 s .

  1. After 1 s , pulse A has moved 1 m to the right and pulse B has moved 1 m to the left.

  2. After 1 s more, pulse A has moved 1 m to the right and pulse B has moved 1 m to the left.

  3. After 5 s , pulse A has moved 5 m to the right and pulse B has moved 5 m to the left.

The idea of superposition is one that occurs often in physics. You will see much, much more of superposition!

Experiment: constructive and destructive interference

Aim

To demonstrate constructive and destructive interference

Apparatus

Ripple tank apparatus

Method

  1. Set up the ripple tank
  2. Produce a single pulse and observe what happens
  3. Produce two pulses simultaneously and observe what happens
  4. Produce two pulses at slightly different times and observe what happens

Results and conclusion

You should observe that when you produce two pulses simultaneously you see them interfere constructively and when you produce two pulses at slightly different times you see them interfere destructively.

Problems involving superposition of pulses

  1. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  2. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  3. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  4. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  5. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  6. For the following pulse, draw the resulting wave forms after 1 s , 2 s , 3 s , 4 s and 5 s . Each pulse is travelling at 1 m · s - 1 . Each block represents 1 m . The pulses are shown as thick black lines and the undisplaced medium as dashed lines.
  7. What is superposition of waves?
  8. What is constructive interference?
  9. What is destructive interference?

Questions & Answers

I'm interested in biological psychology and cognitive psychology
Tanya Reply
what does preconceived mean
sammie Reply
physiological Psychology
Nwosu Reply
How can I develope my cognitive domain
Amanyire Reply
why is communication effective
Dakolo Reply
Communication is effective because it allows individuals to share ideas, thoughts, and information with others.
effective communication can lead to improved outcomes in various settings, including personal relationships, business environments, and educational settings. By communicating effectively, individuals can negotiate effectively, solve problems collaboratively, and work towards common goals.
it starts up serve and return practice/assessments.it helps find voice talking therapy also assessments through relaxed conversation.
miss
Every time someone flushes a toilet in the apartment building, the person begins to jumb back automatically after hearing the flush, before the water temperature changes. Identify the types of learning, if it is classical conditioning identify the NS, UCS, CS and CR. If it is operant conditioning, identify the type of consequence positive reinforcement, negative reinforcement or punishment
Wekolamo Reply
please i need answer
Wekolamo
because it helps many people around the world to understand how to interact with other people and understand them well, for example at work (job).
Manix Reply
Agreed 👍 There are many parts of our brains and behaviors, we really need to get to know. Blessings for everyone and happy Sunday!
ARC
A child is a member of community not society elucidate ?
JESSY Reply
Isn't practices worldwide, be it psychology, be it science. isn't much just a false belief of control over something the mind cannot truly comprehend?
Simon Reply
compare and contrast skinner's perspective on personality development on freud
namakula Reply
Skinner skipped the whole unconscious phenomenon and rather emphasized on classical conditioning
war
explain how nature and nurture affect the development and later the productivity of an individual.
Amesalu Reply
nature is an hereditary factor while nurture is an environmental factor which constitute an individual personality. so if an individual's parent has a deviant behavior and was also brought up in an deviant environment, observation of the behavior and the inborn trait we make the individual deviant.
Samuel
I am taking this course because I am hoping that I could somehow learn more about my chosen field of interest and due to the fact that being a PsyD really ignites my passion as an individual the more I hope to learn about developing and literally explore the complexity of my critical thinking skills
Zyryn Reply
good👍
Jonathan
and having a good philosophy of the world is like a sandwich and a peanut butter 👍
Jonathan
generally amnesi how long yrs memory loss
Kelu Reply
interpersonal relationships
Abdulfatai Reply
What would be the best educational aid(s) for gifted kids/savants?
Heidi Reply
treat them normal, if they want help then give them. that will make everyone happy
Saurabh
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Physics - grade 10 [caps 2011]. OpenStax CNX. Jun 14, 2011 Download for free at http://cnx.org/content/col11298/1.3
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Physics - grade 10 [caps 2011]' conversation and receive update notifications?

Ask