$A$ force $\overrightarrow F = 6\hat i + 2\hat j - 3\hat k$ acts on a particle,causing a displacement of $\overrightarrow s = 2\hat i - 3\hat j + x\hat k$. If the work done is zero,find the value of $x$.

Two particles having position vectors $r_1 = (3 \hat{i} + 5 \hat{j}) \ m$ and $r_2 = (-5 \hat{i} - 3 \hat{j}) \ m$ are moving with velocities $v_1 = (4 \hat{i} + 3 \hat{j}) \ m/s$ and $v_2 = (a \hat{i} + 7 \hat{j}) \ m/s$. If they collide after $2 \ s$,then the value of $a$ is:

$Assertion:$ The total translational kinetic energy of all the molecules of a given mass of an ideal gas is $1.5$ times the product of its pressure and its volume.
$Reason:$ The molecules of a gas collide with each other and the velocities of the molecules change due to the collision.

Which one of the following statements is not correct?

Match the following:

$1$. Burning candle	$i$. Line spectrum
$2$. Sodium vapour	$ii$. Continuous spectrum
$3$. Bunsen flame	$iii$. Band spectrum
$4$. Dark lines in solar spectrum	$iv$. Absorption spectrum

The general formula of a cycloalkane is