List of practice Questions

In a reversible isothermal process,the change in internal energy is :

In a rocket of mass 1000 kg, fuel is consumed at a rate of $40\,kgs^{-1}$ The velocity of gases ejected from rocket is $5\times10^4\,ms^{-1}$ . The thrust on rocket is

In a series $LCR$ circuit, the phase difference between the voltage and the current is $45^?$. Then the power factor will be

In a pure capacitive circuit if the frequency of ac source is doubled, then its capacitive reactance will be

In a reaction involving ring substitution of $C_6H_5Y$ the major product is meta isomer. The group Y can be

In a population per capita birth rate is $0.15$ and per capita death rate is $0.08$ during a unit time period. What is the value of $r$ (intrinsic rate of natural increase) for the given population ?

In a projectile motion, the velocity is perpendicular to acceleration at.

In a plane e.m. wave, magnetic field oscillates sinusoidally with frequency 1 GHz. If its amplitude is $16 \times 10^{-8}$ T then amplitude of electric field is

In a polymer sample, 30% of molecules have a molecular mass of 20,000, 40% have 30,000 and the rest 60,000. What is the weight average molecular mass of the polymer ?

In a polymerase chain reaction, temperature required for the steps (i) Denaturation, (ii) Annealing and (iii) Extension are respectively

In a non leap year the probability of getting 53 Sundays or 53 Tuesdays or 53 Thursdays

In a normal embryosac, the ploidy level of egg cell, polar nuclei, synergids and secondary nucleus is

In a p-n junction diode, the increase in forward voltage of 0.19 V increases the forward current by 37.6 mA. The dynamic resistance of the junction is

In a leap year the probability of having 53 Sundays or 53 Mondays is

In a mature dicot stem which has undergone secondary growth, youngest layer of secondary xylem is situated

In a hexagonal close packed structure (hcp) of spheres, the fraction of the volume occupied by the sphere is A. In a cubic close packed structure, the fraction is B. The relation for A and B is

In a hydrogen atom the total energy of electron is

In a hydrogen atom, the radius of $n^{th}$ Bohr orbit is $r_n$. The graph between $log(r_n/r_1)$ and $logn$ will be

In a group of students, mean weight of boys is 80 kg and mean weight of girls is 50 kg. If the mean weight of all the students taken together is 60 kg, then the ratio of the number of boys so that of girls is

In a head an elastic collision of a very heavy body moving at $v$ with a light body at rest, velocity of the heavy body after collision is

In a healthy adult man, the smallest type of leucocytes are

In a group of 52 persons, 16 drink tea but not coffee, while 33 drink tea. How many persons drink coffee but not tea ?

In a gas equation, PV= RT V refers to the volume of

In a Geiger-Marsden experiment. Find the distance of closest approach to the nucleus of a $7.7 \,MeV$ $\alpha$-particle before it comes momentarily to rest and reverses its direction. ($Z$ for gold nucleus $= 79$)

In a geometric progression consisting of positive terms, each term equals the sum of the next two terms. Then common ratio of the G.P. is