Following are four different relations about displacement, velocity and acceleration for the motion of a particle in general. Choose the incorrect one (s) :

(a) V_av= $\frac{1}{2} [v (t_{1}) + v (t_{2})]$

(b) V_av= $\frac{r {(t}_{2}) - r {(t}_{1})}{t_{2} - t_{1}}$

(c) V_av= $\frac{1}{2} [v (t_{1}) - v (t_{2}) (t_{2} - t_{1})]$

$(d) V a v = \frac{v {(t}_{2}) - v {(t}_{1})}{t_{2} - t_{1}}$

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Vishal Baghel | Contributor-Level 10

4 months ago

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- a, c

Explanation – as we know average acceleration is a_av= $\frac{? v}{? t} = \frac{v_{2} - v_{1}}{t_{2} - t_{1}}$

But when acceleration is not uniform V_av is not equal to v₁+v₂/2

So we can write $? v = \frac{? r}{? t}$

$? r = r_{2} - r_{1}$ = v₂-v₁ (t₂-t₁)

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