CIE A Level Physics復(fù)習(xí)筆記5.1.1 Work & Energy
Work Done
- In Physics,?work is done?when an?object?is?moved?over a distance by an external force applied in the direction of its displacement
- In the diagram below, the man’s pushing force on the block is doing work as it is transferring energy to the block (increasing its kinetic energy)
Work is done when a force is used to move an object over a distanc
- When work is done, energy is transferred from one object to another
- Work done can be thought of as the amount of?energy transferred, hence its units are in?Joules (J)
- Usually, if a?force?acts?in the direction?that an object is moving then the object will?gain energy
- If the?force?acts in the?opposite direction?to the movement then the object will?lose energy
Worked Example
The diagram shows a barrel of weight 2.5 × 103?N on a frictionless slope inclined at 40° to the horizontal.
A force is applied to the barrel to move it up the slope at constant speed. The force is parallel to the slope.What is the work done in moving the barrel a distance of 6.0 m up the slope?
A.? ? ?7.2 × 103?J? ? ? ? ? ? ? ?B.? ? ?2.5 × 104?J? ? ? ? ? ? ? C.? ? ?1.1 × 104?J? ? ? ? ? ? ? ?D.? ? ?9.6 × 103?J
Exam Tip
A common exam mistake is choosing the incorrect force which is not parallel to the direction of movement of an object. You may have to resolve the force vector to find the component that is parallel. The force does not have to be in the same direction as the movement, as shown in the worked example.
轉(zhuǎn)載自savemyexams
以上就是關(guān)于【CIE A Level Physics復(fù)習(xí)筆記5.1.1 Work & Energy】的解答，如需了解學(xué)校/賽事/課程動態(tài)，可至翰林教育官網(wǎng)獲取更多信息。
往期文章閱讀推薦：
翰林獨家 | 經(jīng)濟學(xué)競賽核心精講，一冊打通NEC/IEO/USAEBO！
2026 ALEVEL 夏考A率出爐！愛德思vs牛津AQA，哪些科目真的“好出分”？
翰林AMC8視頻課重磅上線！
國際競賽真題資源免費領(lǐng)取
