List of practice Questions

A boat of mass $40\, kg$ is at rest. A dog of mass $4 \,kg$ moves in the boat with a velocity of $10\, m/s$. What is the velocity of boat?
$v_{rms}, v_{av} $ and $v_{mp}$ are root mean square, average and most probable speeds of molecules of a gas obeying Maxwellian velocity distribution. Which of the following statements is correct?
Drift velocity varies with the velocity of electric field as per the relation
Science which links heredity with environment is
Greatest biological problem which man faces today is
Conifers are found in
Lateral meristem is responsible for
At the time of total solar eclipse, the spectrum of solar radiation will have :
The effective acceleration of a body, when thrown upwards with acceleration $ a $ will be:
just as hydrochloric acid is to pepsinogen, so is
The temperature $(T )$ dependence of resistivity $(r)$ of a semiconductor is represented by
A circular coil of radius $R$ carries an electric current. The magnetic field due to the coil at a point on the axis of the coil located at a distance $r$ from the center of the coil, such that $r > > R$, varies as
Sodium lamps are used in foggy conditions because
A sphere of mass $M$ and radius $R$ is falling in a viscous fluid. The terminal velocity attained by the falling object will be proportional to
A proton and an $\alpha$ - particle, moving with the same velocity, enter into a uniform magnetic field, acting normal to the plane of their motion. The ratio of the radii of the circular paths described by the proton and $\alpha$ - particle is
Mongolism is also known as
Two long conductors, separated by a distance d carry current $I_1$ and $I_2$ in the same direction. They exert a force $F$ on each other. Now the current in one of them increased to two times and its direction reversed. The distance is also increased to $3d$. The new value of the force between them is
In a step-up transformer ratio of number of turns in primary to seconday coil is $1: 25 .$ If input voltage is $230$ volt and load current is $2 \,amp$, then current in primary is :
For a transistor amplifier in common emitter configuration having load impedance of $1\, kO$ ($h_{fe} = 50$ and $h_{oe} = 25$) the current gain is
Which one of the following ores is best concentrated by froth - floatation method?
An ideal gas expands in volume from $1?10^{-3} m^3$ to $1?10^{-2} m^3$ at $300\, K$ against a constant pressure of $1?10^5\, Nm^{-2}$. The work done is
Which of the following sets of quantum numbers is correct for an electron in 4f orbital?
As the temperature is raised from $20^{\circ}C$ to $40^{\circ}C$, the average kinetic energy of neon atoms changes by a factor of which of the following?
When the glancing angle of incidence of light on a material is 30$^\circ$, the reflected and refracted light are found to be perpendicular. The refractive index of material is
Two waves having intensity ratio 25 : 4 produce interference. The ratio of maximum to minima intensity is