费力杠杆:动力臂小于阻力臂,动力大于阻力.费力但是__________.
问题描述:
费力杠杆:动力臂小于阻力臂,动力大于阻力.费力但是__________.
答
费力杠杆:动力臂小于阻力臂,动力大于阻力.费力但是____省距离______.
动力臂x动力=阻力臂x阻力
ps:任何机械都不省功