- 电影与动画
- 音乐
- 宠物和动物
- 运动的
- Travel
- 赌博
- 人与博客
- 新闻与政治
- 操作方法和风格
- 非营利组织和激进主义
- Motivation
- Autos
- Discovery
- Tech Matters & News
- Educational
- Kids Cafe
- Meals
- Behind The Scenes
- Manufacturer's Secret
- Events
- Costumes
- Do It Yourself
- Fashion
- Fitness
- History
- Agriculture
- Success Stories
- Bible Stories
- First Aid
- Articles
- Homes and Interiors
- Babies World
- Sports News
- Book Reviews
- Christian Movies
- Skill Up
- 其他
Human ear - structure & working | Sound | Physics | Khan Academy
Let's explore how human ears work.
More free lessons & practice on this chapter-https://www.khanacademy.org/sc....ience/in-in-class9th
Khan Academy is a nonprofit organisation with the mission of providing a free, world-class education for anyone, anywhere. We offer quizzes, questions, instructional videos, and articles on a range of academic subjects, including math, biology, chemistry, physics, history, economics, finance, grammar, preschool learning, and more. We provide teachers with tools and data so they can help their students develop the skills, habits, and mindsets for success in school and beyond. Khan Academy has been translated into dozens of languages, and 15 million people around the globe learn on Khan Academy every month. As a 501(c)(3) nonprofit organisation, we would love your help!
Created by Mahesh Shenoy