Class 8ScienceSound
Speed of Sound and Echo
Sound needs a medium โ cannot travel in vacuum. Speed in air โ 343 m/s at 25ยฐC. Speed in water โ 1500 m/s. Speed in steel โ 5000 m/s. Echo: reflection of sound from a hard surface. Minimum distance for echo = 17.15 m (so reflected sound arrives after 0.1s). SONAR uses echo to find depth of ocean or detect submarines.
10 examples
Concept check 1
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on concept check and show the working clearly.
Definition to application 2
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on definition to application and show the working clearly.
Formula warm-up 3
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on formula warm-up and show the working clearly.
Reasoning practice 4
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on reasoning practice and show the working clearly.
Board-style short answer 5
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on board-style short answer and show the working clearly.
Mistake correction 6
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on mistake correction and show the working clearly.
Visual interpretation 7
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on visual interpretation and show the working clearly.
Applied word problem 8
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on applied word problem and show the working clearly.
Revision challenge 9
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on revision challenge and show the working clearly.
Exam recap 10
For Class 8 Science, explain or solve a speed of sound and echo question from the chapter "Sound". Focus on exam recap and show the working clearly.