List of practice Questions

A uniform chain of 6 m length is placed on a table such that a part of its length is hanging over the edge of the table. The system is at rest. The co-efficient of static friction between the chain and the surface of the table is 0.5, the maximum length of the chain hanging from the table is ____m.
 A vertical electric field of magnitude 4.9 × 105 N/C just prevents a water droplet of a mass of 0.1 g from falling. The value charge on the droplet will be(Given g = 9.8 m/s2)

Among Co3+, Ti2+, V2+ and Cr2+ ions, one if used as a reagent cannot liberate H2 from dilute mineral acid solution, its spin-only magnetic moment in gaseous state is________ B.M. (Nearest integer)

Among the following species
N2,N2+,N2−,N22−,O2,O2+,O2−,O22−
the number of species showing diamagnetism is ________.

Choose the correct option from the following options given below :

Choose the correct order of density of the alkali metals.

Consider the following metal complexes:
[Co(NH3)6]3+
[CoCl(NH3)5]2+
[Co(CN)6]3–
[Co(NH3)5(H2O)]3+
The spin-only magnetic moment value of the complex that absorbs light with shortest wavelength is _______ B.M. (Nearest integer)

Drugs used to bind to receptors, inhibiting its natural function and blocking a message are called:

During the denaturation of proteins, which of these structures will remain intact?

If m is the slope of a common tangent to the curves
\(\frac{x²}{16} + \frac{y²} {9} = 1\)
and x2 + y2 = 12, then 12m2 is equal to:

If the mean deviation about the mean of the numbers 1, 2, 3, …. n, where n is odd, is \(\frac{5(n + 1)}{n}\), then n is equal to ______.
If the sum of the co-efficients of all the positive even powers of x in the binomial expansion of \((2x^3+\frac{3}{x})^{10} \) is 510 – β·39, the β is equal to ____.
If the system of equations αx + y + z = 5, x + 2y + 3z = 4, x + 3y +5z = β has infinitely many solutions, then the ordered pair (α, β) is equal to:
If \(y = m_1x + c_1 \)and \(y = m_2x + c_2\), \(m_1≠m_2\) are two common tangents of circle \(x_2 + y_2 = 2\) and parabola \(y^2 = x\), then the value of \(8|m_1m_2|\) is equal to :

In a potentiometer arrangement, a cell gives a balancing point at 75 cm length of wire. This cell is now replaced by another cell of unknown emf. If the ratio of the emf’s of two cells respectively is 3 : 2, the difference in the balancing length of the potentiometer wire in above two cases will be _____ cm.

 In the given reaction,
The number of chiral carbon(s)
(where Et is –C2H5)
The number of chiral carbon(s) in product A is ______.
Incorrect statement for Tyndall effect is:
Let \(\vec a=a_1\hat i+a_2\hat j+a_3\hat k\), \(a_i>0,\ i=1, 2, 3\) be a vector which makes equal angles with the coordinate axes OX, OY and OZ. Also, let the projection of \(\vec a\) on the vector \(3\hat i+4\hat j\) be 7. Let \(\vec b\) be a vector obtained by rotating \(\vec a\) with 90°. If \(\vec a,\vec b\) and x-axis are co-planar, then projection of a vector \(\vec b\) on \(3\hat i+4\hat j\) is equal to :
Let a circle C touch the lines L1 : 4x – 3y +K1 = 0 and L2 : 4x – 3y + K2 = 0, K1, K2∈R. If a line passing through the centre of the circle C intersects L1 at (–1, 2) and L2 at (3, –6), then the equation of the circle C is :
Let d be the distance between the foot of perpendiculars of the point P(1, 2, –1) and Q(2, –1, 3) on the plane –x + y + z = 1. Then d2 is equal to ____.
Let l1 be the line in xy-plane with x and y intercepts ⅛ and \(\frac{1}{4√2} \) respectively and l2 be the line in zx-plane with x and z intercepts -⅛ and \(−\frac{1}{6√3}\) respectively. If d is the shortest distance between the line l1 and l2, then d–2 is equal to ______.

Let
ƒ : R → R
be defined as f(x) = x -1 and
g : R - { 1, -1 } → R
be defined as
g(x) = \(\frac{x²}{x² - 1}\)
Then the function fog is :

\(lim(x→\frac{x}{2}) tan^2x((2sin^2x+3sinx+4)^{\frac{1}{2}}-(sin^2x+6sinx+2)^{\frac{1}{2}}\) is equal to.

Match List-I with List-II.

List-IList-II
(A) N2(g) + 3H2(g) → 2NH3(g)(I) Cu
(B) CO(g) + 3H2(g) → CH4(g) + H2O(g)(II) Cu/ZnO – Cr2O3
(C) CO(g) + H2(g) → HCHO(g)(III) FexOy + K2O + Al2O3
(D) CO(g) + 2H2(g) → CH3OH(g)(IV) Ni

Choose the correct answer from the options given below :

Melamine polymer is formed by the condensation of :