List of practice Questions

A voltage \( v = v_0 \sin(\omega t) \) applied to a circuit drives a current \( i = i_0 \sin(\omega t + \phi) \) in the circuit. The average power consumed in the circuit over a cycle is:
Which one of the following correctly represents the change in wave characteristics (all in vacuum) from microwaves to X-rays in electromagnetic spectrum?
In which compound does Mn (Manganese) have its highest oxidation state?
The formula of sodium nitroprusside is:
The speed of light in two media '1' and '2' are \( v_1 \) and \( v_2 \) (\( v_2>v_1 \)) respectively. For a ray of light to undergo total internal reflection at the interface of these two media, it must be incident from:
What is the correct expression for the molar conductivity (\( \Lambda^\circ_m \)) of Al\(_2\)(SO\(_4\))\(_3\) at infinite dilution?
A source produces monochromatic light of frequency \( 5.0 \times 10^{14} \, \text{Hz} \) and the power emitted is 3.31 mW. The number of photons emitted per second by the source, on an average, is:
Biuret test is not given by:
Paraffin wax is:
Which of the following figures correctly represent the shape of the curve of binding energy per nucleon as a function of mass number?
Copper on reaction with moist air gives:
When a p-n junction diode is forward biased:
The best indicator for titrating 0.1 N Na2CO3 against 0.1 N HCl is:
The bond dissociation energies of gaseous H2, Cl2, and HCl are 104, 58, and 103 kcal, respectively. The enthalpy of formation of HCl gas would be:
Let \( \lambda_e \), \( \lambda_p \), and \( \lambda_d \) be the wavelengths associated with an electron, a proton, and a deuteron, all moving with the same speed. Then the correct relation between them is:
In a Bowler's solution containing the same concentrations of B- and HB, the ratio of KB to B- is 10-10. The pH of the Bowler's solution will be:

Assertion (A): The potential energy of an electron revolving in any stationary orbit in a hydrogen atom is positive. 
Reason (R): The total energy of a charged particle is always positive.

A projectile of mass 200 g is launched in a viscous medium at an angle $60^\circ$ with the horizontal, with an initial velocity of 270 m/s. It experiences a viscous drag force $\vec{F} = -c \vec{v}$ where the drag coefficient $c = 0.1 \, \text{kg/s}$ and $\vec{v}$ is the instantaneous velocity of the projectile. The projectile hits a vertical wall after 2 s. Taking $e = 2.7$, the horizontal distance of the wall from the point of projection (in m) is ____
Benzene on ozonolysis followed by reaction with Zn + H2O gives:

Assertion (A): We cannot form a p-n junction diode by taking a slab of a p-type semiconductor and physically joining it to another slab of an n-type semiconductor.
Reason (R): In a p-type semiconductor, \( n_e \gg n_h \) while in an n-type semiconductor \( n_h \gg n_e \).

Assertion (A): The deflection in a galvanometer is directly proportional to the current passing through it.
Reason (R): The coil of a galvanometer is suspended in a uniform radial magnetic field.
What is the enthalpy of neutralization for CH3COOH + NaOH?

Assertion (A): It is difficult to move a magnet into a coil of large number of turns when the circuit of the coil is closed.
Reason (R): The direction of induced current in a coil with its circuit closed, due to motion of a magnet, is such that it opposes the cause.

Show that \( \mathbf{E} = \rho \mathbf{J} \) leads to Ohm's law. Write a condition in which Ohm's law is not valid for a material.
What does sodium phthalate give on reaction with sodalime?