Opening of floral buds into flowers is a type of

Let $a, b, c$ be distinct non-negative numbers. If the vectors $a \hat{i} + a \hat{j} + c \hat{k}$,$\hat{i} + \hat{k}$,and $c \hat{i} + c \hat{j} + b \hat{k}$ lie in a plane,then $c$ is:

The $pK_a$ of a weak acid is $4.8$. What should be the ratio of $\frac{[\text{acid}]}{[\text{salt}]}$,if a buffer of $pH=5.8$ is required?

$A$ body of mass $1\,kg$ crosses a point $O$ with a velocity $60\,ms^{-1}.$ $A$ force of $10\,N$ directed towards $O$ begins to act on it. It will again cross $O$ in ........ $\sec$.

The equation of a stationary wave along a stretched string is given by $y = 5 \sin \frac{2\pi}{3}x \cos 40\pi t$,where $x$ and $y$ are in $cm$ and $t$ is in $s$. The separation between two adjacent nodes is ..... $cm$.

The potential energy for a force field $\vec{F}$ is given by $U(x, y) = \cos(x + y)$. The force acting on a particle at the position given by coordinates $(0, \pi/4)$ is: