List of top Questions asked in NEET (UG)- 1999

The resistance of a discharge tube is
When air is replaced by a dielectric medium of constant K, the maximum force of attraction between two charges separated by a distance
Dichotomous branching is found in
What is the effective capacitance between points X and y?
Aquatic reptiles are
The internal resistance of a cell of e.m.f. 2 V is $0.1\, \Omega$ It is connected to a resistance of $3.9\, \Omega$. The voltage across the cell will be
The current in the given circuit is
Which of the following fern is an excellent biofertilizer?
0 .15 g of a substance dissolved in 15 g of a solvent higher by 0.216$^\circ$C than that of the pure solvent. Find out the molecular weight of the substance. $(K_b\, for\, solvent \, is\, 2.16 ^\circ C)$
The type of hybridization of boron in diborane is
Tablets to prevent male contraception contain
Life span of a worker bee is
Temperature changes, in the environment, affect most of the animals which are
The de-Broglie wavelength of a particle with mass 1 g and velocity 100 m/s is
The uncertainty in momentum of an electron is $1\times 10^{-5} kg m/s.$ The uncertainty in its position will be (Given, $h = 6.62 \times 10^{-34} kg m^2/s)$
The number of atoms in 4.25 g of $NH_3$ is approximately
Wavelength of light of frequency 100 Hz
The escape velocity of a sphere of mass m is given by (G = Universal gravitational constant; M = Mass of the earth and R = Radius of the e earth)
If a unit vector is represented by $ 0.5 \widehat{ i} - 0 . 8 \widehat{j} + c \widehat{k}$ then the value of c is
The closing and opening of the leaves of Mimosa pudica is due to
A straight wire of diameter 0.5 mm carrying a current of 1 A is replaced by the another wire of 1 mm diameter carrying the same current. The strength of the magnetic field far away is
Sympathetic neural system induces

Energy transfer from one trophic level to another, in a food chain, is

Rate of heart beat is determined by
Cholecystokinin and duocrinin are secreted by