The angle between the lines represented by $(\sin^2 \alpha) y^2 - 2xy(\cos^2 \alpha) + (\cos^2 \alpha - 1) x^2 = 0$ is

An electrolytic cell contains a solution of $Ag_2SO_4$ and has platinum electrodes. $A$ current is passed until $1.6 \ g$ of $O_2$ has been liberated at the anode. The amount of silver deposited at the cathode would be ............. $g$.

Which one of the following elements,when present as an impurity in silicon,makes it a $p$-type semiconductor?

Let $f$ be a non-zero real-valued continuous function satisfying $f(x+y)=f(x) \cdot f(y)$ for all $x, y \in R$. If $f(2)=9$,then $f(6)$ is equal to

Water rises in a capillary tube of radius $r$ to a height $h$. The mass of water in the capillary is $m$. What will be the mass of water that rises in a capillary tube of radius $\frac{r}{3}$?

$A$ point moves with uniform acceleration and $v_1, v_2$ and $v_3$ denote the average velocities in the three successive intervals of time $t_1, t_2$ and $t_3$. Which of the following relations is correct?