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The relation between time t and distance x is t = α x² + β x, where α and β are constants. The relation between acceleration (a) and velocity (v) is

Asked in JEE Main 31st Jan 1st Shift 2024 · Velocity- and position-dependent acceleration

Answer: (2) a = -2α v³

Step-by-step solution

Differentiate t = α x² + β x with respect to x: (dt)/(dx) = 2α x + β, so v = (dx)/(dt) = 1/(2α x + β).

(dv)/(dx) = -(2α)/((2α x + β)²) = -2α v².

Chain rule: a = (dv)/(dt) = v(dv)/(dx) = v(-2α v²) = -2α v³.

Why the other options are wrong

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