The area of the parallelogram formed by vectors $\vec{P} = 2\hat{i} - \hat{j} + 5\hat{k}$ and $\vec{Q} = 3\hat{i} - 2\hat{j} + 4\hat{k}$ is

Given $|\vec{A}_1| = 2$,$|\vec{A}_2| = 3$,and $|\vec{A}_1 + \vec{A}_2| = 3$. Find the value of $|(\vec{A}_1 + 2\vec{A}_2) \times (3\vec{A}_1 - 4\vec{A}_2)|$.

Why is $\vec{v} \times \vec{p} = 0$ for a particle moving in a straight line,and how does this relate to the angular momentum of a rotating particle?

Let $\vec{A} = 2 \hat{i} - 3 \hat{j} + 4 \hat{k}$ and $\vec{B} = 4 \hat{i} + \hat{j} + 2 \hat{k}$,then $|\vec{A} \times \vec{B}|$ is equal to:

Two forces $\vec F_1 = 5\hat i + 10\hat j - 20\hat k$ and $\vec F_2 = 10\hat i - 5\hat j - 15\hat k$ act on a single point. The angle between $\vec F_1$ and $\vec F_2$ is nearly . . . . . . $^\circ$.

$A$ vector $\vec{A}$ points towards North and vector $\vec{B}$ points upwards,then $\vec{A} \times \vec{B}$ points towards ...........