List of practice Questions

A resonance tube closed at one end is of height $1.5\ \text{m}$. A tuning fork of frequency $340\ \text{Hz}$ is vibrating above the tube. Water is poured in the tube gradually. The minimum height of water for which resonance is obtained is (Neglect end correction. Speed of sound in air = $340\ \text{m/s}$)

For a certain organ pipe, three successive resonant frequencies are heard as $300\ \text{Hz}$, $420\ \text{Hz}$ and $540\ \text{Hz}$. If the speed of sound in air is $360\ \text{m/s}$, then the pipe is a

A plane surface of area $200\ \text{cm^2}$ is kept in a uniform electric field of intensity $200\ \text{N/C}$. If the angle between the normal to the surface and the field is $60^\circ$, then the electric flux through the surface is $\left[\cos 60^\circ = \dfrac{1}{2}\right]$

The frequency of a tuning fork is $220\ \text{Hz}$ and the velocity of sound in air is $330\ \text{m/s}$. When the tuning fork completes $80$ vibrations, the distance travelled by the wave is

What is the least radius of curve on a horizontal road, at which a vehicle can travel with a speed of $36\ \text{km/h}$ at an angle of inclination $45^\circ$? $\left[g = 10\ \text{m/s}^2,\ \tan 45^\circ = 1\right]$

Forces $\vec{P}$ and $\vec{Q}$ have resultant $\vec{R}$ whose magnitude is $40\ \text{N}$. $\vec{R}$ makes an angle $45^\circ$ with $\vec{P}$ as well as $\vec{Q}$. The magnitude of $\vec{P}$ is $\left(\tan \dfrac{\pi}{4} = 1\right)$

Time taken by sunlight to penetrate $2\ \text{mm}$ through a glass slab is of the order $\left[\text{Refractive index of glass} = 1.5,\ \text{velocity of light in air} = 3 \times 10^8\ \text{m/s}\right]$

A block of mass $1\ \text{kg}$ is kept on an ice surface. When a velocity of $4\ \text{m/s}$ is given to it, it stops by friction in $5\ \text{s}$. The coefficient of friction is $\left[g = 10\ \text{m/s}^2\right]$

Force $F = P + Qt + \dfrac{1}{r + xs} + c\sin(\omega t + \phi)$ where $x$ and $t$ represent displacement and time respectively. The dimensions of the product $cs$ are

If a capillary tube is immersed vertically in water, rise of water in capillary is $h_1$. When the whole arrangement is taken to a depth $d$ in a mine, the water level rises to $h_2$. The ratio $\dfrac{h_2}{h_1}$ is $\left(R = \text{radius of earth}\right)$

A radar of power $1\ \text{kW}$ operating at frequency $10\ \text{GHz}$ is located on a mountain top of height $500\ \text{m}$. The maximum distance upto which it can detect object located on the surface of the earth is $\left[\text{Radius of earth} = 6.4 \times 10^6\ \text{m}\right]$

For the weight of a body of mass $5\ \text{kg}$ to be zero on equator of the earth, angular velocity of the earth must be $\left[\text{Radius of earth} = 6400\ \text{km},\ g = 10\ \text{m/s}^2\right]$

A uniform disc of mass $4\ \text{kg}$ has radius $0.4\ \text{m}$. Its moment of inertia about an axis passing through a point on its circumference and perpendicular to its plane is

Two bodies rotate with kinetic energies $E_1$ and $E_2$. Moment of inertia about their axis of rotation is $I_1$ and $I_2$. If $I_1 = \dfrac{I_2}{3}$ and $E_1 = 27E_2$, then the ratio of the angular momentum $L_1$ to $L_2$ is

For three non-zero vectors $\vec{A}$, $\vec{B}$ and $\vec{C}$, $\vec{A} + \vec{B} = \vec{C}$ and $A^2 + B^2 = C^2$, then the angle between $\vec{A}$ and $\vec{B}$ will be

A resistance of $100\ \Omega$, inductor of self-inductance $\left(\dfrac{4}{\pi^2}\right)\ \text{H}$ and a capacitor of unknown capacitance are connected in series to an a.c. source of $200\ \text{V}$ and $50\ \text{Hz}$. When the current and voltage are in phase, the capacitance and power dissipated respectively are

If $\Delta H^\circ$ and $\Delta S^\circ$ for the reaction $N_2O_4(g) \rightarrow 2NO_2(g)$ is $57.24\ \text{kJ}$ and $175.8\ \text{J K}^{-1}\text{mol}^{-1}$ respectively, what is the value of $\Delta G^\circ$ for this reaction at $298\ \text{K}$?

What is the number of atoms in $12.08 \times 10^{23}$ unit cells if an element crystallises in bcc structure?

What is the oxidation number of V in $V_2O_7^{4-}$ ion?

Upper surface of tongue bears many projections called ___________.

Considering the given diagram, select the correct option with respect to labels ‘A’ and ‘B’.

Which of the following is a fungal disease?

The most effective, cheapest and convenient method to protect plants from pathogens is ___________.

The saprophytes like bacteria, actinomycetes and fungi are ___________.