List of practice Questions

A tuning fork of frequency $512\, Hz$ makes $4$ beats per second with the vibrating string of a piano. The beat frequency decreases to $2$ beats per sec when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was
Electromagnets are made of soft iron because soft iron has
Which of the following species is not electrophilic in nature ?
A galvanometer has a coil of resistance $100\, ohm$ and gives a full scale deflection for $30\, mA$ current. If it is to work as a voltmeter of $30\, volt$ range, the resistance required to be added will be
A ball moving with velocity $2\, m/s$ collides head on with another stationary ball of double the mass. If the coefficient of restitution is $0.5$, then their velocities $(in\, m/s)$ after collision will be
A particle of mass $M$, starting from rest, undergoes uniform acceleration. If the speed acquired in time $T$ is $V$, the power delivered to the particle is
A condenser of capacity $C$ is charged to a potential difference of $V_1$. The plates of the condenser are then connected to an ideal inductor of inductance $L$. The current through the inductor when the potential difference across the condenser reduces to $V_2$ is
A current loop consists of two identical semicircular parts each of radius $R$, one lying in the $x-y$ plane and the other in $x-z$ plane. If the current in the loop is $i$. The resultant magnetic field due to the two semicircular parts at their common centre is
A $0.66\, kg$ ball is moving with a speed of $100 \,m/s$. The associated wavelength will be $(h = 6.6 \times 10^{-34} \, Js)$
An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to
Liquid hydrocarbons can be converted to a mixture of gaseous hydrocarbons by
Consider the following relations for emf of a electrochemical cell : (a) emf of cell = (Oxidation potential of anode) - (Reduction potential of cathode) (b) emf of cell = (Oxidation potential of anode) + (Reduction potential of cathod) (c) emf of cell = (Reduction potential of anode) + (Reduction potential of cathode) (d) emf of cell = (Oxidation potential of anode) - (Oxidation potential of cathode) Which of the above relations are correct ?
A circular disk of moment of inertia it is rotating in a horizontal plane, about its symmetry axis, with a constant angular speed $\omega_i$. Another disk of moment of inertia $I_b$ is dropped coaxially onto the rotating disk. Initially the second disk has zero angular speed. Eventually both the disks rotate with a constant angular speed $\omega_f$. The energy lost by the initially rotating disc to friction is
The fruit fly Drosophila melanogaster was found to be very suitable for experimental verification of chromosomal theory of inheritance by Morgan and his colleagues because :
The genotype of a plant showing the dominant phenotype can be determined by
Vasa eflferentia are the ductules leading from
What does the electronic configuration $ 1s^2, \, 2s^2, \, 2p^ 5 , \, 3s^1 $ indicate ?
The resistance of 1 N solution of acetic acid is 250 $\Omega$, when measured in a cell of cell constant $1.15 cm ^{-1}$. The equivalent conductance (in $ohm^{-1} cm^2 equiv^{-1}) $of 1 N acetic acid is
The density of glycerol is higher than propanol due to
Which type of dyes are not used do dye nylon and polyester fibres?
The pair of straight lines $ {{x}^{2}}-3{{y}^{2}}=0 $ and the line $ x=1 $ form a triangle which is
Compound that has smell of bitter almonds is
Ethyl alcohol cannot be used as a solvent for methyl magnesium iodide because
A can filed with water is revolved in a vertical circle of radius 4 m and the water does not fall down. The time period for a revolution is about
The crystal structure can be studied by using