- firstly are force, motion, work, energy all in different sections.
- machines(topic) is both mixture of complicated and simple.
- what is effort arm
Kindly refer to the link given below to get the answer of your IIIrd statement :
https://www.meritnation.com/ask-answer/question/what-is-load-arm-and-effort-arm/work-and-energy/3994392
https://www.meritnation.com/ask-answer/question/what-is-load-arm-and-effort-arm/work-and-energy/3994392