Experimental device for verify law of conservation of mechanical energy

The utility model provides a vacuum cap that experimental device for verify law of conservation of mechanical energy, it include two the same to are furnished with two dishes of bleeding of forming a complete set with the vacuum cap, it is equipped with air exhaust nozzle and control flap to bleed to coil, all hang the same pendulum ball through the cycloid in every vacuum cap, pendulum ball is can be by the hollow iron ball of magnetic force attraction, the texture and the length of two cycloids are the same, the outside limit of two vacuum caps is all placed and is used for holding pendulum ball's electro -magnet by magnetic force. To originally directly tell or calculate the law of conservation of mechanical energy who draws through the theory, make the form that experiment directly perceived adds scientific reasoning into, help the student directly perceived, perceptually understand the physical law, trained the scientific reasoning ability. Utilize the current vacuum cap in physics laboratory, bleed set, equipment experiment such as vacuum aspiration pump, not only save the cost, have still that the equipment is easy, convenient operation's advantage, promote broad prospect.