List of practice Questions

If the power factor changes from $\frac{1}{2}\,to\,\frac{1}{4}$ ,then what is the increase in impedance in A.C. ?

If the pressure in a closed vessel is reduced by drawingbut some gas, the mean free path of the molecules

If the pressure of a gas contained in a closed vessel increases by $x$ % when heated by $1^{\circ}C$, its initial temperature is

If the non-zero numbers $x, y, z$ are in A.P. and $\tan^{-1}x, \tan^{-1}y, \tan^{-1}z$ are also in A.P., then

If the normal to the curve $y^2 = 5x - 1$, at the point (1,- 2) is of the form ax - 5y + b = 0, then a and b are:

If the $p^{th}$, $q^{th}$ and $r^{th}$ terms of a G.P. are again in G.P., then which one of the following is correct?

If the mean of the first n odd natural number be n itself, then n is

If the mean of the squares of first n natural numbers be 11, then n is equal to

If the median and the range of four numbers {x, y, 2x + y, x - y}, where 0 < y < x < 2y, are 10 and 28 respectively, then the mean of the numbers is :

If the mean of numbers $27, 31, 89, 107, 156$ is $82$, then the mean of $130, 126, 68, 50, 1$ is

If the mean of n observations $1^2, 2^2, 3^2....,n^2$ is $\frac{46n}{11}$ , then n is equal to

If the lines $\frac{x+1}{2} = \frac{y-1}{1} = \frac{z+1}{3} $ and $\frac{x+2}{2} = \frac{y-k}{3} =\frac{z}{4} $ are coplanar, then the value of k is :

If the matrix AB = O, then

If the mean deviation about the median of the numbers a, 2a,.......,50a is 50, then | a | equals

If the mean deviation of the numbers 1, 1 + d, 1 + 2d, .... 1 + 100d from their mean is 255, then d is equal to :

If the mean of first n natural numbers is equal to $\frac{n + 7}{3}$, then n is equal to

If the length of three sides of a trapezium other than base are equal to $10 \,cm$, then find the area of trapezium when it is maximum.

If the line $3x - 4y + 5 = 0$ is a tangent to the parabola $y^2 = 4ax,$ then $a$ is equal to

If the line $ax + by + c = 0$ is a tangent to the curve $xy = 4,$ then

If the line joining $(2, 3, -1)$ and $(3, 5, -3)$ is perpendicular to the line joining $(1, 2, 3)$ and $(3, 5, \lambda)$, then $A =$

If the internal bisector of $\angle AOB$ where $O = (0, 0, 0), A= (3, 4, 12), B = (1, 2, 2)$ intersects AB at C then $C_y$ =

If the ionisation energy of hydrogen atom is $13.6\,eV$, the energy required to excite it from ground state to the next higher state is approximately

If the $j^{th}$ term and $k^{th}$ term of an A.P. are k and j respectively, the ( k + j) th term is:?

If the leaves on the stem show distichous condition, the

If the general formula for aldehyde is written as ${C_n H_{2n+1}CHO}$, the value of n for isobutyraldehyde is