The oscillating system of the spring pendulum is a spring and a load attached to it. The mass of the spring and the elasticity of the load are neglected and it is believed that all the mass is concentrated in the load, and the spring has elasticity. Friction is neglected. The oscillatory system of a mathematical pendulum is a small weight suspended on a long thread. The dimensions of the weight are neglected in comparison with the length of the thread and the weight of the thread compared to the weight of the weight. The thread is considered inextensible. friction is neglected.
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