List of practice Questions

A black hole is an object whose gravitational field is so strong that even light cannot escape from it. To what approximate radius would earth (mass $= 5.98 \times 10^{24} \, kg$) have to be compressed to be a black hole?

An analysis of chromosomal DNA using the Southern hybridization technique does not use

Light with an energy flux of $ 25 \times 10^4 W m^{-2} $ falls on a perfectly reflecting surface at normal incidence. If the surface area is $ 15 c m^2 $, the average force exerted on the surface is

A projectile is fired from the surface of the earth with a velocity of $5\, m s^{- 1}$ and angle $\theta$ with the horizontal. Another projectile fired from another planet with a velocity of $3\,ms^{ - 1}$ at the same angle follows a trajectory which is identical with the trajectory of the projectile fired from the earth. The value of the acceleration due to gravity on the planet is (in $ms^{ - 2}$ ) is (Given $g= 9.8 \,ms^{ - 2}$)

Five kingdom system of classification suggested by R.H. Whittaker is not based on

Which of the following organic compounds has same hybridisation as its combustion (CO$_2$) product?

Among the following sets of reactants which one produces anisole?

A monoatomic gas at a pressure $P$, having a volume $V$ expands isothermally to a volume $2V$ and then adiabatically to a volume $16\,V$. The final pressure of the gas is (Take $\gamma =5/3 )$

A transformer having efficiency of 90% is working on $200\, V$ and $3 \,kW$ power supply. If the current in the secondary coil is $6\, A$, the voltage across the secondary coil and the current in the primary coil respectively are

Injury localized to the hypothalamus would most likely disrupt

The resistances in the two arms of the meter bridge are $5\, \Omega$ and $R\, \Omega$ respectively. When the resistance $R$ is shunted with an equal resistance, the new balance point is at $1.6l_1$. The resistance $R$ is

A conducting sphere of radius $R$ is given a charge $Q$. The electric potential and the electric field at the centre of the sphere respectively are

Fruit colour in squash is an example of

What is the percentage of free space in body centered cubic unit cell?

A particle is moving such that its position coordinates (x, y) are (2 m, 3 m) at time t = 0, (6 m, 7 m) at time t = 2 s and (13 m, 14 m) at time t = 5 s. Average velocity vector $ ( \vec{ v_{av}})$ from t = 0 to t = 5 s is .

When the gas expands with temperature using the relation $ V=KT^{2/3} $ for the temperature change of $ 40\,K, $ the work done is

Which quantity is transmitted with propagation of longitudinal waves through a medium?

Mass number of an atom is the sum of

Which of the following relation is called mirror equation?

A car moving on a straight road covers $ 1/3 $ of the distance with $ 25\,km/h $ and rest with $ 75\,km/h $ . The average speed is

All substances that conduct electricity in aqueous solutions are called?

Find the length of the diagonal of the parallelepiped formed by planes drawn through the points $ (2,3,5) $ and $ (5,9,7), $ parallel to the co-ordinate planes?

For transistor the value of $ \beta $ is $50$ then, the value of $\alpha$ is

Light from a point source in air falls on a spherical glass surface ( $ n=1.67 $ and radius of curvature $ =25\,cm $ ). The distance of the light source from the glass surface is $ 95\,cm $ . At what position, the image is formed?

In acidic medium, $H_2O_2 $ changes $ Cr_2O_7^{2-} $ to $CrO_5 $ which has two (-O-O-) bonds. Oxidation state of Cr in $CrO_5 $ is