If $$P, Q$$ and $$R$$ are physical quantities having different dimensions, which of the following combinations can never be a meaningful quantity?
The given graph shows the variation of velocity $$v$$ with position $$x$$ for a particle moving along a straight line
Which of the following graph shows the variation of acceleration a with position x?
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The trajectory of a projectile projected from origin is given by the equation $$y=x-\frac{2 x^2}{5}$$. The initial velocity of the projectile is
An object with mass $$5 \mathrm{~kg}$$ is acted upon by a force, $$\mathbf{F}=(-3 \hat{\mathbf{i}}-4 \hat{\mathbf{j}}) \mathrm{N}$$. If its initial velocity at $$t=0$$ is $$\mathbf{v}=(3 \hat{\mathbf{i}}+12 \hat{\mathbf{j}}) \mathrm{m} / \mathrm{s}$$, the time at which it will just have a velocity along $$y$$-axis is -