In a head-on elastic collision of two bodies of equal masses

suppose two bodies having initial velocities as, u1 and u2 and final as v1 and v2. Then we know that, and also,

So, we can see that velocities are interchanged, hence A and B are true. As masses are same, so momenta are change too. And also, by changing of velocity, slow body speeds up and vice-verse.


So, all are correct.









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