As we know, v=dtdx.
Given, xP(t)=αt+βt2
Velocity of bus P is vP=dtdxP=α+2βt and velocity of bus Q is vQ=f−2t
When vP=vQ
⇒α+2βt=f−2t
⇒f−α=2(β+1)t⇒t=2(β+1)f−α
JEE Main 2022 — Physics Mechanics
Two buses P and Q start from a point at the same time and move in a straight line and their positions are represented by xP(t)=αt+βt2 and xQ(t)=ft−t2. At what time, both the buses have same velocity ?
Held on 25 Jun 2022 · Verified 6 Jul 2026.
1+βα−f
2(β−1)α+f
2(1+β)α+f
2(1+β)f−α
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