IB DP Physics: HL复习笔记2.3.1 Kinetic Energy
Kinetic Energy
- Kinetic energy (Ek) is the energy an object has due to its motion (or velocity)
- The faster an object is moving, the greater its kinetic energy
- When an object is falling, it is gaining kinetic energy since it is gaining speed
- This energy transferred from the gravitational potential energy it is losing
- An object will maintain this kinetic energy unless its speed changes
- Kinetic energy can be calculated using the following equation:
Kinetic energy (KE): The energy an object has when it is moving
Derivation of Kinetic Energy Equation
- A force can make an object accelerate; work is done by the force and energy is transferred to the object
- Using this concept of work done and an equation of motion, the extra work done due to an object's speed can be derived
- The derivation for this equation is shown below:
Worked Example
A body travelling with a speed of 12 m s–1 has kinetic energy 1650 J.If the speed of the body is increased to 45 m s–1, estimate what is its new kinetic energy.
Exam Tip
When using the kinetic energy equation, note that only the speed is squared, not the mass or the ½.If a question asks about the ‘loss of kinetic energy’, remember not to include a negative sign since energy is a scalar quantity.
转载自savemyexams
以上就是关于【IB DP Physics: HL复习笔记2.3.1 Kinetic Energy】的解答，如需了解学校/赛事/课程动态，可至翰林教育官网获取更多信息。
往期文章阅读推荐：
生物竞赛金牌教练的实战书单！生物学/生物化学/病理学...电子版免费领！
哈佛商学院2026暑期书单曝光！十余位教授私藏书单，本本是“商科天花板”
翰林AMC8视频课重磅上线！
国际竞赛真题资源免费领取
