杠杆供中学物理做“杠杆平衡条件”学生分组及教师演示实验。
J2119 Lever
For the students in group to make experiment on “the conditions of equilibrium of a lever” and for the teacher to demonstrate how a lever is used.
J2119 Lever
For the students in group to make experiment on “the conditions of equilibrium of a lever” and for the teacher to demonstrate how a lever is used.
