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An object of mass m collides with a stationary object of mass m at its initial velocity v. after the collision, the momentum of the two objects is equal. The possibility of M / M is obtained
It tells you a rule: the relative velocity of two objects before and after collision does not increase (for fully elastic collision, the relative velocity does not change; for general inelastic collision, the relative velocity decreases)
According to the conservation of momentum, the total momentum before and after the collision remains unchanged, but the momentum after the collision is equal, so the velocity of M becomes V / 2. For m, according to MV / 2 = mu, the velocity u = MV / 2m
U and V are obviously in the same direction, then according to the Law mentioned at the beginning, we can get 0 ≤ U-V / 2 ≤ v
The range of M / M is obtained by solving the inequality
1≤M/m≤3
For the formula of velocity, I know two. One is v = (V1 + V2) number 2, and then 2 (V1 + V2) divided by v1.v2
Under what conditions are these two formulas used?
If the average velocity of the first half is V1 and the average velocity of the second half is V2, then the former v = (V1 + V2) / 2 is the average velocity of the whole course. If the average velocity of the first half is V1 and the average velocity of the second half is V2, then the latter v = 2v1 V2 / (V1 + V2) is the average velocity of the whole course
The formula of relative velocity is: v = | V 1-V 2 | / √ (1-V 1V 2 / C ^ 2) the velocity of two objects is v 1, V 2, the difference between them is V, over
The classical relative velocity the classical relative velocity is a simple formula of addition and subtraction. For example, the velocity of the river is V (relative to the ground), and the velocity of the boat in still water is u (relative to the ground). If the boat goes downstream, the velocity of the boat relative to the ground is v. = u + V. on the contrary, if the boat goes upstream, the boat relative to the ground
RELATED INFORMATIONS
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