A block of mass 3 kg is placed on a rough surface with friction 3N and is pulled by a force F .
What is the magnitude of F when the block moves with constant speed ?
Physics (Force)
2006-12-09 4:09 am
回答 (1)
2006-12-09 4:15 am
✔ 最佳答案
3N, the force is used to overcome the friction force.But, if the block is at rest at the beginning, more than 3N is required.
It is because 3N is used to overcome friction, other force would then used to accelerate the block (F=ma);
Once move, for the block have constant speed, 3N is already enough.
參考: CE Physics
收錄日期: 2021-04-23 16:28:58
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https://hk.answers.yahoo.com/question/index?qid=20061208000051KK03741