Derivation process of stiffness coefficient relationship of series spring? Series connection: stiffness coefficient relation 1 / k = 1 / K1 + 1 / K2 How to deduce? The detailed process is needed If you can, add the parallel derivation process. But the best answer is to look at the series

Derivation process of stiffness coefficient relationship of series spring? Series connection: stiffness coefficient relation 1 / k = 1 / K1 + 1 / K2 How to deduce? The detailed process is needed If you can, add the parallel derivation process. But the best answer is to look at the series

The top is the spring K1, the bottom is the K2, connected together, and the bottom is the weight g, then for K2, the elongation L1 = g / K2; the upper K1 elongation L1 = g / K1, the total elongation L = L1 + L2 = g / K1 + G / K2, and for the spring in series, l = g / K, the two equations are combined, and 1 / k = 1 / K1 + 1 / K2 in parallel: see the following figure (I can't

Formula derivation of velocity and acceleration of spring release!
The vertical spring compresses L1 and stores energy of 200J. If a 3kg object is pressed positively and suddenly loosens, the formula of velocity and acceleration is derived. If the spring is not vertical, but is at a certain angle with the ground, but the weight is perpendicular to the spring axis
Add. A 3kg object has friction coefficient u = 0 with other objects. The weight of the spring itself is not taken into account. The original purpose of this problem is to meet the needs of the process, which requires that the object with an angle of 3kg from the horizontal plane complete a distance L2 displacement at the speed of 0.2m/s. Using the method of spring energy storage to achieve the design of the spring. Then there is another problem 2, that is, after the spring energy storage is released, first empty the stroke L3, and then collide with a 3kg object and displace L2 together, (the 3kg object has friction coefficient with other objects, u = 0). 2) It is stopped by the stroke baffle. The design of spring
The differential equations are listed and solved according to the meaning of the problem. I hope my description is correct.

According to the integral of F = KX a = KX / m, the spring work w = 1 / 2 * KX & # 178 is deduced; here x = L1, f = 3xg, g = 9.8, w = 200J, since the thing of 3kg is pressed first and does not move, it is proved that the spring is forced at this time. Suppose g = 9.8, 3x9.8 = 29.4n and 29.4 = kl1, k = 29.4/l1. Because the spring is static at the beginning, the instantaneous speed of sudden release is 0
When the 3kg object is taken away, the restoring force of the spring becomes an internal force, f = ma, a = f / m
I don't know which stage of the topic, high school? Graduate? So is it an ideal state? What's the weight of the spring itself? And so on. There are not many conditions for the topic. I really don't know how to answer it
I'm very confused about this question, so I can only answer here. Brother, I tried my best

A ball with a mass of M and a velocity of V collides with a ball with a mass of 3M. The collision is elastic or inelastic
A ball with mass m and velocity V collides with a ball with mass 3M at rest. The collision is elastic or inelastic, and the velocity of B ball may be?
0.6v 0.4v 0.2v
The calculated elastic collision is V1 '= - 0.5V V2' = 0.5V
Inelastic is 0.25V, how to judge next? Reason

There is no energy loss in elastic collision, which is the critical value of the maximum velocity of B, and the maximum energy loss in inelastic collision, which is the critical value of the minimum velocity of B, so V is between 0.5 and 0.25, which is 0.4V