List of practice Questions

Which of the following is used as a moderator in nuclear reaction?

In Young?s experiment, the monochromatic light is used to illuminate two slits $A$ and $B$ as shown. Interference fringes are observed on a screen placed in front of the slits. Now if a thin glass plate is placed normally in the path of beam coming from the slit $A$, then

Diode is used as a/an

Energy is not carried by which of the following wave?

Boolean algebra is essentially based on

A particle of mass $ m $ moving with velocity $ v $ collides with a stationary particle of mass $ 2m $ . The speed of the system, will be:

The reaction responsible for the production of light energy from the sun is

In n-type semiconductors, majority charge carriers are

Kidney of adult reptiles are

An animal, which is diploblastic and radially symmertrical is:

In sponges, circulation of waler in flagellated chamber is facilitated by:

Two identical circular loops of metal wire are lying on a table without touching each other. Loop A carries a current which increases with time. In response, the loop B

The ratio of the speed of sound in nitrogen gas to that in helium gas, at 300 K. is

The oxidation number of sulphur in $S_8 , S_2F_2, H_2S$ respectively, are

The normality of 0.3 M phosphorus acid $(H_3PO_3)$ is

The coordination number of metal crystallising in a hexagonal close packing is

Let $PQR$ be a right angled isosceles triangle, right angled at $P (2,1)$. If the equation of the line $QR$ is $2x + y = 3$, then the equation representing the pair of lines PQ and PR is

Ionic radii of

For a positive integer n let $a (n) = 1 + \frac{1}{2} + \frac{1}{3} + \frac{1}{4} + ...+ \frac{1}{(2^n)-1},$ then

The harmonic mean of the roots of the equation $ (5+\sqrt 2)\, x^2 - (4+\sqrt 5)\, x + 8 + 2\sqrt5 = 0 $ is

For a positive integer n, let $f_n(\theta)=\Bigg(tan\frac{\theta}{2}\Bigg)(1+sec \theta)(1+sec 2\theta)(1+ sec 2^2 \theta)... (1+sec 2^n \theta), then$

Let $a_1,a_2,...,a_{10}$ be in AP and $h_1, h_2$ equal to .....,$h_{10}$ be in HP. If $a_1 = h_1 = 2$ and $ a_{10} = h_{10} = 3,$ then $a_4 h_7$ is

If in the expansion of $(1 + x)^m (1 - x)^n$, the coefficients of $x$ and $x^2$ are 3 and - 6 respectively, then m is euqal to

$ lim_{ n \to \infty} \frac{1}{n} \displaystyle \sum_{r = 1}^ {2n} \frac{r}{ \sqrt{ n^2 + r^2}} $ equals

Let $ S_1, S_2,...$ be squares such that for each $ n \ge 1 $ the length of a side of $ S_n $ equals the length of a diagonal of $ S_{n+1}$. If the length of a side of $ S_1 $ is 10 cm, then for which of the following values of n is the area of $S_n$ less than 1 sq cm?