List of practice Questions

Cuscuta is an example of

$50\, mL$ of each gas A and of gas B takes $150$ and $200\, s$ respectively for effusing through a pin hole under the similar conditions. If molecular mass of gas B is $36,$ the molecular mass of gas A will be

In a reaction, A + B $\rightarrow$ Product, rate is doubled when the concentration of B is doubled and rate increases by a factor of 8 when the concentrations of both the reactants (A and B) are doubled. Rate law for the reaction can be written as

When $Cl_2$ gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from

A solid cylinder of mass $3\, kg$ is rolling on a horizontal surface with velocity $4\, ms^{-1}$. It collides with a horizontal spring of force constant $200\, N\, m^{-1}$. The maximum compression produced in the spring will be

The potential energy of a particle in a force field is $ U=\frac{A}{r^2}-\frac{B}{r}$ where A and B are positive constants and r is the distance of particle from the centre of the field. For stable equilibrium, the distance of the particle is

Two spheres $A$ and $B$ of masses $m_1$ and $m_2$ respectively collide. $A$ is at rest initially and $B$ is moving with velocity $v/2$ along x-axis. After collision $B$ has a velocity in a direction perpendicular to the original direction. The mass $A$ moves after collision in the direction

A spherical planet has a mass $M_p$ and diameter $D_p$. A particle of mass $m$ falling freely near the surface of this planet will experience an acceleration due to gravity, equal to

A geostationary satellite is orbiting the earth at a height of $5\,R$ above that surface of the earth, $R$ being the radius of the earth. The time period of another satellite in hours at a height of $2\,R$ from the surface of the earth is

The height at which the weight of a body becomes $1 / 16^{\text {th }}$, its weight on the surface of earth (radius R), is

If the radius of a star is $R$ and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is $ Q ? $ ($ \sigma $ stands for Stefan's constant)

In the circuit shown the cells A and B have negligible resistances. For $V_A =12\, V,\, R_1 =500\, \Omega $ and $ R =100\, \Omega $ the galvanometer (G) shows no deflection. The value of $V_B$ is

What is the flux through a cube of side a if a point charge of q is at one of its corner?

A car of mass $1000 \,kg$ negotiates a banked curve of radius $90\,m$ on a frictionless road. If the banking angle is $45^{\circ}$, the speed of the car is

A car of mass m is moving on a level circular track of radius R.If $\mu_s$ represents the static friction between the road and tyres of the car, the maximum speed of the car in circular motion is given by

A car of mass m starts from rest and accelerates so that the instantaneous power delivered to the car has a constant magnitude $P_0$. The instantaneous velocity of this car is proportional to

A certain gas takes three times as long to effuse out as helium. Its molecular mass will be:

A circular platform is mounted on a frictionless vertical axle. Its radius R = 2 m and its moment of inertia about the axle is $ 200\, kg\, m^2 $. It is initially at rest. A 50 kg man stands on the edge of the platform and begins to walk along the edge at the speed of $ 1 \,ms^{-1} $ relative to the ground. Time taken by the man to complete one revolution is

The gynoecium consists of many free pistils in flowers of

A particle has initial velocity $ ( 2 \vec{i} + 3 \vec{j})$ and acceleartion ($ 0 . 3 \vec{i} + 0 . 2 \vec{j})$ The magnitude of velocity after 10 seconds will be

A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number ?

Which one of the following statements regarding photochemical smog is not correct?

Vernalization stimulates flowering in

Limiting molar conductivity of $NH_4OH $ $[i.e. \,\wedge^\circ {m (NH_4OH)}]$ is equal to

A milli voltmeter of $25$ milli volt range is to be converted into an ammeter of $25$ ampere range. The value (in ohm) of necessary shunt will be