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A=x2 find velocity when x is 2m given at x=0 body is at rest |
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Answer» Acceleration and displacement are RELATED as a = x² we know, acceleration , a = \bf{v\FRAC{dv}{dx}}v dx dv
so, x² = \bf{v\frac{dv}{dx}}v dx dv
⇒x²dx = vdv ⇒∫x²dx = ∫vdv at x = 0 , BODY is in rest ∴ initial velocity , v₀ = 0 Let velocity at x = 2 is v Now, \bf{\int\limits^{2}_0{x^2}\,dx=\int\limits^v_0{v}\,dv} 0 ∫ 2
x 2 dx= 0 ∫ v
vdv ⇒ [x³/3]²₀ = \bf{[\frac{v^2}{2}]^v_0 ⇒8/3 = v²/2 ⇒16/3 = v² So, v = ±4/√3 m/s Hence, magnitude of velocity = 4/√3 m/s |
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